r/gcc • • Aug 02 '24

r/GCC refers to the entire GNU compiler suite, not specifically the binary named 'gcc' that compiles C.

12 Upvotes

In other words, this is not a dedicated C-language subreddit. In the sidebar, do notice that r/C_programming and r/cpp_questions also exist.


r/gcc • • Aug 07 '26

GCC 16.2 Released

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21 Upvotes

r/gcc • • 4d ago

GNU Tools Weekly News Week 56 (September 20, 2026)

7 Upvotes

Release updates for GNU toolchain:
 * GDB 18.1.0 update
  * https://inbox.sourceware.org/gdb-patches/87se32aoq1.fsf@redhat.com
  * Release is this Friday!

GNU toolchain conference reminders:
 *  GNU Tools Cauldron 2026, Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
 * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
   * https://lpc.events/event/20/abstracts/

General/big GNU toolchain news:
 * Syncing Rust GCC ["JIT"] backend or how to test Murphy's law
  * https://blog.guillaume-gomez.fr/articles/2026-09-22+Syncing+Rust+GCC+backend+or+how+to+test+Murphy%27s+law
 * Meeting minutes - Office Hours for the GNU Toolchain - 2026-09-17
  * https://inbox.sourceware.org/gcc/190c0f1d-cbe9-4fe2-be74-58c6042667b1@redhat.com/
  * https://gcc.gnu.org/wiki/OfficeHours
 *

GCC easy issue to tackle of the week:
 *  `(a&-a) < 0` -> `a == INT_MIN`
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126627
  *  Reach out to Andrea Pinski <[andrew.pinski@oss.qualcomm.com](mailto:andrew.pinski@oss.qualcomm.com)> for
mentoring on this issue.
 * Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

GCC commits:
 * https://gcc.gnu.org/r17-4212 ... r17-4502 -  291 commits
  * Improve saturated unsigned add detection
  * https://gcc.gnu.org/r17-4218 https://gcc.gnu.org/r17-4219
 * gccrs sync
  * https://gcc.gnu.org/r17-4278 ... https://gcc.gnu.org/r17-4360
 * Improve some code in std::vector::push_back
  * https://gcc.gnu.org/r17-4377-ge548eb628c689e
https://gcc.gnu.org/r17-4378-gedb9556068ae47
 * contrib, libcpp, libstdc++: Update to Unicode 18.0.0
  * https://gcc.gnu.org/r17-4409-g20a1e5b5c5addc
 * aarch64: Add support for FEAT_CMH atomic {store,load} intrinsics
  * https://gcc.gnu.org/r17-4448-gd5a076158aa3da
https://gcc.gnu.org/r17-4449-g4015b65b038bea
 * phiopt: Better pre-vect heurstics for factoring out loads
  * https://gcc.gnu.org/r17-4456-gb1dcde565577e8
 * cselim: cond_if_else_store_replacement_limited support skipping on
store one either side
 * https://gcc.gnu.org/r17-4469-ge35b8dad030bc4

GCC discussion:
 *

GCC bugzilla stats
 *  140 new issues filed
 *  55 issues closed

binutils/gdb commits:
 * RISC-V: Add Zama16b extension support
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=59db9002142a655b4d5e4af7cbf0605aaddefc7e
 * RISC-V: Add support for ziccamoc extension.
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=cd2166234b9e6569b1cf8a4169e58f487996c447

gdb discussion:
 *
binutils discussion:
 *
glibc commits:
 * aarch64: Add MTE mode tunable
  * https://sourceware.org/cgit/glibc/commit/?id=8f6dfd399a97c77ea6855a5eb28a6babb81ec31c
 * math: Update tanh from CORE-MATH
  * https://sourceware.org/cgit/glibc/commit/?id=1c8c9998d803897d5765fab8c68ad9b0db6f7444
 * malloc: Improve calloc
  * https://sourceware.org/cgit/glibc/commit/?id=4b4de574ad95ffbee25b4aed3891275fd769ff3c
 *
glibc discussion:
 * glibc buildbot status
  * https://inbox.sourceware.org/libc-alpha/20260920192938.GG2330@gnu.wildebeest.org/


r/gcc • • 4d ago

GNU Tools Weekly News Week 57 (September 27, 2026)

4 Upvotes

Release updates for GNU toolchain:
 * GDB 18.1.0 was released
  * https://inbox.sourceware.org/gdb/announce.6ab698d7.84bf0792.34ed8d.a212@mx.google.com/

GNU toolchain conference reminders:
 *  GNU Tools Cauldron 2026
  * This Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
 * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
  * https://lpc.events/event/20/abstracts/

General/big GNU toolchain news:
 *

GCC easy issue to tackle of the week:
 *  Missed optimization in math expression: optimize float / in some cases
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83715
  * Hint, this is like previous one: https://gcc.gnu.org/PR126745;
though slightly more involved due to float rules
  *  Reach out to Andrea Pinski <[andrew.pinski@oss.qualcomm.com](mailto:andrew.pinski@oss.qualcomm.com)> for
mentoring on this issue.
 * Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

GCC commits:
 * https://gcc.gnu.org/r17-4503 ... r17-4705 -  203 commits
 * match: Fold redundant integer-float-integer conversions
  * https://gcc.gnu.org/r17-4503-gd0e28326d4254e
 * match: fold extract-bitfield-and-shift expressions
  * https://gcc.gnu.org/r17-4511-g885ad73e630ca2
 * aarch64: Improve isnan, isfinite, isinf and isnormal and fpclassify
  * https://gcc.gnu.org/r17-4523-ge8fb8ba77cf7a1
  * https://gcc.gnu.org/r17-4524-g52330debcdf1fc
  * https://gcc.gnu.org/r17-4525-g5cc9ef64063c45
 * match: fold abs(x) comparisons with x
  * https://gcc.gnu.org/r17-4549-g59c8c4bbac4657
 * Improve libstdc++ rege
  * https://gcc.gnu.org/r17-4552 https://gcc.gnu.org/r17-4553
  * https://gcc.gnu.org/r17-4554 https://gcc.gnu.org/r17-4555
 * AArch64: Turn off outline atomics with -mcmodel=large
  * https://gcc.gnu.org/r17-4655-gee5bf81d7816b0
 * simplify-rtx: [SU]MUL_HIGHPART RTL simplifications
  * https://gcc.gnu.org/r17-4656-gd382f953805cb0
 * C++26 P3769R1: Clarification of placement new deallocation as a DR
  * https://gcc.gnu.org/r17-4658-geed9f52920aa36
 * range-ops: derive operand equality from a zero MINUS_EXPR
  * https://gcc.gnu.org/r17-4663-gbddea69ee406a0
 * match.pd: Fold (a != 0) | (popcount(a) == n) and related patterns
  * https://gcc.gnu.org/r17-4693-g56efa4a739786b
 * vect: Look through promotions for SAT_TRUNC
  * https://gcc.gnu.org/r17-4697-g19378ecd385156
 * middle-end: fold VEC_UNPACK_LO/_HI over poly constants
  * https://gcc.gnu.org/r17-4593-g1743eb860b739c

GCC discussion:
 *
GCC bugzilla stats
 *  123 new issues filed
 *  63 issues closed

binutils/gdb commits:
 * LoongArch: Enable shared library and PIE support for loongarch*-elf
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=196286d25ccc652dc086ae173d1cfa836bed0618
 * RISC-V: Enable shared library and PIE support for riscv*-elf
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=b73d23cccf5568321cabaad3a8ec5cddafdef4ec
 * RISC-V: Add optional register argument to tail pseudo
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=441953ac9d0b2902be92906817c68feadccd190f

gdb discussion:
 *
binutils discussion:
  *
glibc commits:
 * math: Sync lgamma, acosf, exp10m1f, and tgamma with CORE-MATH
  * https://sourceware.org/cgit/glibc/log/?id=90156a65a6318b2e1a5ef44501f50fe87db1b601&qt=range&q=90156a65a6318b2e1a5ef44501f50fe87db1b601...1555d46b08dba3a9abbcd956237108b3072f4290%5E
 * AArch64: Add SVE2 memchr
  * https://sourceware.org/cgit/glibc/commit/?id=3edeb81021feff11a3d0e934d68446f6a67dd1a3
 *
glibc discussion:
 * segfault after reallocation (Was: malloc: Change mmap chunk layout)
  * https://inbox.sourceware.org/libc-alpha/armngyyT1otFqpSq@end/


r/gcc • • 4d ago

RepoOS: An AI-driven, formally verified, open source, Python-to-MLIR compiler for zero-overhead execution

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0 Upvotes

r/gcc • • 18d ago

GNU Tools Weekly News Week 55 (September 13, 2026)

1 Upvotes

Release updates for GNU toolchain:
* GDB 18.1.0 update
* Release didn't happen, some bugs came up; delayed until the 25th
* https://inbox.sourceware.org/gdb-patches/87h5jscjhu.fsf@redhat.com/
* GCC 13.5.0 was released
* https://inbox.sourceware.org/gcc/952104o8-0r3s-oq9q-7619-q1o3r58p4ssq@fhfr.qr/

GNU toolchain conference reminders:
* GNU Tools Cauldron 2026, October 2-4 (Prague)
* https://gcc.gnu.org/wiki/cauldron2026
* https://conf.gnu-tools-cauldron.org/prg26/cfp
* Toolchains Track at LPC 2026, October 7th (Prague)
* https://lpc.events/event/20/abstracts/

General/big GNU toolchain news:
* gccrs August 2026 Monthly report
* https://inbox.sourceware.org/gcc/8b7f85ea-4cf2-413b-9c88-87d4bd829f46@opensrcsec.com/
* Implementation of GCC's Nested Functions
* https://uecker.codeberg.page/2026-09-05.html

GCC easy issue to tackle of the week:
* `a << CST >> CST` can be simplified into a if upper CST bits of a
are known to be zero
* https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126644
* Reach out to Andrea Pinski andrew.pinski@oss.qualcomm.com for
mentoring on this issue.
* Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

GCC commits:
* https://gcc.gnu.org/r17-3967 ... r17-4211 - 245 commits
* ifcvt: Handle arm-only diamond live-outs
* https://gcc.gnu.org/r17-3970-g301afaab5b8eaf
* middle-end: Improve bitreverse RTL expansion with AOP.
* https://gcc.gnu.org/r17-3977-gfb21f1686938d6
* match/fold: support (a CMP b) OP (a CMP b) for more OPs
* https://gcc.gnu.org/r17-4001-gbbc2517fe41307
https://gcc.gnu.org/r17-4000 https://gcc.gnu.org/r17-3999
* ranger: loads from constant tables of floats a range
* https://gcc.gnu.org/r17-4024-gc1b5260244cf53
* Recognize CLZ loop for signed non-negative values
* https://gcc.gnu.org/r17-4047-ge90e0f66051d33
* gccrs merge: 43 commits
* https://gcc.gnu.org/r17-4130-g4d9b51c8cb1317 ...
https://gcc.gnu.org/r17-4088-gb276fbcc9d8ad0
* phiopt: Support constants for cond_store_replacement_limited
* https://gcc.gnu.org/r17-4133-g230d950810f378
* GIMPLE FE: clobber parsing
* https://gcc.gnu.org/r17-4148-g9ed526efc2f6ab
* match: `A - MIN (B, C)` to `A + MAX (-B, -C)`
* https://gcc.gnu.org/r17-4209-g771f488a90f748
* match: branchless min and max folds
* https://gcc.gnu.org/r17-4210-g9d734bb468e714
* rs6000: Add support for _BitInt
* https://gcc.gnu.org/r17-4163-g83998f47450c08

GCC bugzilla stats
* 143 new issues filed
* 129 issues closed

binutils/gdb commits:
* RISC-V: Support Zvabd version 0.9
* https://sourceware.org/cgit/binutils-gdb/commit/?id=720f87fd856c31aaf13bd264285fda97376f2535
* RISC-V: Add Sspmp extension support
* https://sourceware.org/cgit/binutils-g


r/gcc • • 21d ago

GCC 13.5 Released with 256+ bugs fixed, closing the release series.

Thumbnail gcc.gnu.org
26 Upvotes

r/gcc • • 25d ago

GNU Tools Weekly News Week 54 (September 6, 2026)

7 Upvotes

Release updates for GNU toolchain:
 * GDB 18.1.0 update
  * https://inbox.sourceware.org/gdb-patches/874ig9t4s5.fsf@redhat.com/
 * GCC 13.5.0 update
  * RC1 was published
  * https://inbox.sourceware.org/gcc/9r6n9o16-7on9-62rn-9r08-251o692n7oo5@fhfr.qr/
  * https://inbox.sourceware.org/gcc/ns42774p-s754-16so-205n-77110r4p6ss5@fhfr.qr/
GNU toolchain conference reminders:
 * GNU Tools Cauldron 2026, Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
 * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
  * https://lpc.events/event/20/abstracts/

General/big GNU toolchain news:
 * rustc_codegen_gcc: Progress Report #43
  * https://blog.antoyo.xyz/rustc_codegen_gcc-progress-report-43
 * Kito Cheng is now the RISCV binutils maintainer
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=250c0280ba546e85315bafbc820c1b70242d8e6e

GCC easy issue to tackle of the week:
 * (int)(((unsigned)a) + CST) should be simplified into a + CST if
a+CST is known not to overflow in int
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126751
  *  Reach out to Andrea Pinski <[andrew.pinski@oss.qualcomm.com](mailto:andrew.pinski@oss.qualcomm.com)> for
mentoring on this issue.
 * Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

GCC commits:
 * https://gcc.gnu.org/r17-3775 r17-3966 -  192 commits
 * forwprop: add simplify_phi_result_movdiv
  * https://gcc.gnu.org/r17-3791-g5b40e9d181bfe2
 * match: Fold CPROJ when nested inside CPROJ or CABS
  * https://gcc.gnu.org/r17-3801-g0e0ddac529e215
 * middle-end: add const fold for various crc builtins
  * https://gcc.gnu.org/r17-3816-g26238368615c0a
 * x86: ACEv1 support
  * https://gcc.gnu.org/r17-3847 https://gcc.gnu.org/r17-3848
https://gcc.gnu.org/r17-3849
  * https://gcc.gnu.org/r17-3850 https://gcc.gnu.org/r17-3851
https://gcc.gnu.org/r17-3852
  * https://gcc.gnu.org/r17-3853
 * libcpp: Optimize Arm search_line_fast
  * https://gcc.gnu.org/r17-3868-gffc5227ac2e198
 * RISC-V: Add MVENDORID, MARCHID and MIMPID for 6 RISC-V cores
  * https://gcc.gnu.org/r17-3882-gd3d6b2a1fba366
 * RISC-V: Support -mtune=native and -mcpu=native
  * https://gcc.gnu.org/r17-3883-gbbc5005bf48212
 * RISC-V: Add TImode and OImode move expanders.
  * https://gcc.gnu.org/r17-3906-ge096b2205f81b3
 * match: Simplify MIN(A, B) eq/ne 0 to A when B is positive
  * https://gcc.gnu.org/r17-3779-g09fe63bb71e6b1

GCC discussion:
 *

GCC bugzilla stats
 *  84 new issues filed
 *  63 issues closed

binutils/gdb commits:
 * RISC-V: Add support for XAndes* extensions
  * https://sourceware.org/cgit/binutils-gdb/log/?id=ce6455998599d6a8af6f4aea8813392921e4e86c&qt=range&q=%0948c933a69a890e7769ca8a01570aab578b6a9f54...ce6455998599d6a8af6f4aea8813392921e4e86c
 * RISC-V: Add support for XXTVarith and XXTVcoder extensions
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=f67471902997e528e789ed27f1bf930318052ecc
 * x86: support further AMD Zen6 instructions
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=99f119ca28d9d38766dc08c880d421ce126ab48a

gdb discussion:
 *

binutils discussion:
 *

glibc commits:
 *

glibc discussion:
 *


r/gcc • • Aug 31 '26

GNU Tools Weekly News Week 53 (August 30, 2026)

3 Upvotes

Release updates for GNU toolchain:
 * GDB 18.1.0 update
  * delayed until September 11th
  * https://inbox.sourceware.org/gdb-patches/87y0dvtz84.fsf@redhat.com/T/

GNU toolchain conference reminders:
 * GNU Tools Cauldron 2026, Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
  * cfp closes August 31st (tomorrow)
 * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
  * https://lpc.events/event/20/abstracts/

General/big GNU toolchain news:
 * Sourceware Infrastructure news - AI scrapping and website throttling
  * https://inbox.sourceware.org/gcc/0475bd28feb9f78dcea1c13d6315aac79966ca53.camel@klomp.org/
 * Accuracy of Mathematical Functions (glibc)
  * https://inbox.sourceware.org/libc-alpha/p9u0wltelndm.fsf@thym/

GCC easy issue to tackle of the week:
 *  umax(a,b)==0 folding into a|b==0 gets in the way sometimes
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126880
  *  Reach out to Andrea Pinski <[andrew.pinski@oss.qualcomm.com](mailto:andrew.pinski@oss.qualcomm.com)> for
mentoring on this issue.
 * Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

GCC commits:
 * https://gcc.gnu.org/r17-3568 r17-3774-  207 commits
 * RISCV: Support -mcpu=native
  * https://gcc.gnu.org/r17-3578 https://gcc.gnu.org/r17-3577
https://gcc.gnu.org/r17-3577
 * RISCV: Add sifive-p550 and sifive-p870-d
  * https://gcc.gnu.org/r17-3579-g7ca5288cc68ff5
 * hoist invariants after unswitching
  * https://gcc.gnu.org/r17-3584-g66ed104db50c63
 * genmatch: Don't emit the ssa name checks for cond^
  * https://gcc.gnu.org/r17-3612-gf77f607c42df40
 * range: add VREL_EQ relation effect for div and mod
  * https://gcc.gnu.org/r17-3610-g7c25b09da5841c
  * Easy issue for week 50
 * phiopt: replicate conditionals over a PHI of comparisons
  * https://gcc.gnu.org/r17-3622-g804ff22702eca4
 * aarch64: Support FCCMP and FCCMPE for _Float16
  * https://gcc.gnu.org/r17-3628-g263ce2e907f722
 * libstdc++: optional: Treat _M_engaged as being assumed to be false
after the destructor
  * https://gcc.gnu.org/r17-3656-ge982f847aab9f7
 * aarch64: allow usage of zero reg for CRC32 instructions
  * https://gcc.gnu.org/r17-3684-g004a9da1bde785
 * c-family: honor explicit -Wstrict-aliasing under -fno-strict-aliasing
  * https://gcc.gnu.org/r17-3685-g39ba948f9b86e1
 * aarch64: Recognize vector permute patterns which can be optimized
as REV64+EXT
  * https://gcc.gnu.org/r17-3712-g4182cf11e1e3d2
 * c++: unshare RANGE_EXPR CONSTRUCTOR index
  * https://gcc.gnu.org/r17-3765-g40cbcd4eedce58
 *

GCC discussion:
 *

GCC bugzilla stats
 *  125 new issues filed
 *  95 issues closed

binutils/gdb commits:
 * x86: Support AVX10_V2_AUX instructions
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=84b5fe5be98582a247346f4fba8072f286498dad
 *

gdb discussion:
 *
binutils discussion:
 *
glibc commits:
 * math: Update tanh from CORE-MATH (revision bb39e4fa)
  * https://sourceware.org/cgit/glibc/commit/?id=70cc22b19c2037097f0f0cce89488763c6c49f5b
 * x86: Update AVX10 support
  * https://sourceware.org/cgit/glibc/commit/?id=56f3aed8bb8be64d1a78488a427e7c61c7c866cf
 *
glibc discussion:
 *


r/gcc • • Aug 24 '26

GNU Tools Weekly News Week 52 (August 23, 2026)

5 Upvotes

Release updates for GNU toolchain:
 *

GNU toolchain conference reminders:
 * GNU Tools Cauldron 2026, Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
  * cfp closes August 31st
 * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
  * https://lpc.events/event/20/abstracts/

General/big GNU toolchain news:
 * Notes from Office Hours for the GNU Toolchain - 2026-08-20
  * https://inbox.sourceware.org/gcc/e6206e50-a3e6-428f-965f-eee240a9b3a0@redhat.com/
  * https://gcc.gnu.org/wiki/OfficeHours
 * GSOC final report: GCC Rust - Compiling the 'alloc' Crate
  * https://inbox.sourceware.org/gcc/287dcedc2af29cfbeccfb667f7fb879f@purelymail.com/
  * https://gccrs.nsvke.com/
 * GSOC final report:Rust Drop trait support in gccrs
  * https://inbox.sourceware.org/gcc/CAHtgQQsUO3dmh4Bi20ScAnwgVfxKzPq6weu-hiMs4YtzyAxP-Q@mail.gmail.com/
 * GSOC final report: Extending C++ Support in -fanalyzer
  * https://inbox.sourceware.org/gcc/DKWAQJXY3M07.A5RD6NB1BUF0@gmail.com/

GCC easy issue to tackle of the week:
 *  smax(a,-a) -> abs for RTL
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126726
  *  Reach out to Andrea Pinski <[andrew.pinski@oss.qualcomm.com](mailto:andrew.pinski@oss.qualcomm.com)> for
mentoring on this issue.
 * Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

GCC commits:
 * https://gcc.gnu.org/r17-3321 ... r17-3567  247 commits
 * allow backward threading to loop exit
   * https://gcc.gnu.org/r17-3330-g4fe2072d5d16ce
 * match.pd: turn more conditional bit_iors unconditional
  * https://gcc.gnu.org/r17-3334-g656bb1d9e96370
 * ranger-op: Handle some relational comparison for some operations
  * https://gcc.gnu.org/r17-3335 r17-3336
 * AVR: Add option for strict address space subset relations
  * https://gcc.gnu.org/r17-3340-gcbf217f4c7076d
 * x86: Add Sub-byte element extraction and Symmetric-signed
saturation narrow support
  * https://gcc.gnu.org/r17-3338-gd3c381c7010c05
 * Recognize long-multiply into regular multiply
  * https://gcc.gnu.org/r17-3437 ... https://gcc.gnu.org/r17-3443
 * ranger: Teach ranger about POLY_INT_CST ranges for VRP.
  * https://gcc.gnu.org/r17-3518-g1dd02e1deffddc
  * https://gcc.gnu.org/r17-3519-ga3fb4bf350d6b7
 * range: Add some non-negative function support
  * https://gcc.gnu.org/r17-3553-g53799b81fad8cd
 * sccp: Handle variable trip count XOR in final value replacement
  * https://gcc.gnu.org/r17-3460-g62993cc9d2200e
 * libstdc++: Optimize chrono year::is_leap
  * https://gcc.gnu.org/r17-3387-g28b1b55c60464d

GCC discussion:
 * GSOC reports: see general big GNU toolchain news section

GCC bugzilla stats
 * 110 new issues filed
 *  76 issues closed

binutils/gdb commits:
 * gdb: Fix for ifunc malloc
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=de930032d883219559d1dba575f2c0f5359e80fc
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=ca0908d623605250e6d84afb90d742c328e6bb90
 * gdb: Prevent downgrading of hardware watchpoints if possible
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=7ee28b5aee4eaadffadf1df9a555a7737e5e744c

gdb discussion:
 *
binutils discussion:
 *
glibc commits:
 * malloc: aarch64: Add ifuncs for malloc functions (add back after
gdb fix; see above)
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=7ee28b5aee4eaadffadf1df9a555a7737e5e744c
glibc discussion:
 *


r/gcc • • Aug 17 '26

GNU Tools Weekly News Week 51 (August 16, 2026)

5 Upvotes

Release updates for GNU toolchain:
 * GDB 18.1 release update
  * https://inbox.sourceware.org/gdb-patches/877bls4t5f.fsf@redhat.com/
 *
GNU toolchain conference reminders:
 * GNU Tools Cauldron 2026, Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
  * cfp closes August 31st
 * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
  * https://lpc.events/event/20/abstracts/

General/big GNU toolchain news:

GCC easy issue to tackle of the week:
 * a==b imples (a+b)&1 is known to 0
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126877
  * Like previous week, a range improvement
  *  Reach out to Andrea Pinski <[andrew.pinski@oss.qualcomm.com](mailto:andrew.pinski@oss.qualcomm.com)> for
mentoring on this issue.
 * Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

GCC commits:
 * https://gcc.gnu.org/r17-3173 ... r17-3320 148 commits
 * Simplify ((X CMP1 Y) - (X CMP2 Y)) REL 0
  * https://gcc.gnu.org/r17-3190-gc59bee6acb24a0
 * match.pd: Fold abs(x) * abs(y) -> abs(x * y)
  * https://gcc.gnu.org/r17-3200-g7c48d6a74693e1
 * c++26: Change alignof (decltype (^^::)) from 1 to alignof (void *)
  * https://gcc.gnu.org/r17-3213-g89c1412dfc26d1
* x86-64: Add -m128bit-atomic
  * https://gcc.gnu.org/r17-3230-gd9e21f7c4d1666
  * https://www.phoronix.com/news/GCC-Git-m128bit-atomic
 * aarch64: Add SME2p3/SVE2p3 x2 narrowing right shift intrinsics
  * https://gcc.gnu.org/r17-3226-gf49cb8938ef3ab
 * match: Try to remove casts for `(int)-(unsigned)a`
  * https://gcc.gnu.org/r17-3279-g8d004ef91c4f7c

GCC discussion:
 * Missing copyright header
  * https://inbox.sourceware.org/gcc/e38642cc-0096-428f-b83c-0bb25c1f5314@gmail.com/
 * RFC: Should -fplugin and -fplugin-arg options be excluded from
DW_AT_producer recording?
  * https://inbox.sourceware.org/gcc/CY5PR02MB899172AD2B298297BCE46F73E2DC2@CY5PR02MB8991.namprd02.prod.outlook.com/
 * DW_OP_GNU_uninit emitted with -gstrict-dwarf
  * https://inbox.sourceware.org/gcc/CAEyVarHYT=o+xyA4snHmSgS3A+YBz=DO2ZtOAe7uat3sY2WfHw@mail.gmail.com/
 *

GCC bugzilla stats
 * 139 new issues filed
 *  80 issues closed

binutils/gdb commits:
 * aarch64: Implement Structured Exception Handling (SEH) on AArch64
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=17afc47d8bc304f527eb58ea8086a39fdc0cbd19
 * Mark TIC6X binutils port unmaintained
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=7e7dd6cfcf60cda2506d19d88ff98622bf670dbd
 *
gdb discussion:
 *
binutils discussion:
 *
glibc commits:
 *
glibc discussion:
 *


r/gcc • • Aug 16 '26

Verifiable C / Using Proof Helpers with GCC

8 Upvotes

Let me get this out of the way first: I am not doing anything safety critical. I just want to find ways to make more stable software, even if said ways are more advanced. I understand that GCC, whilst being very stable, hasn't been verified like CompCert. I just am curious if proof helpers can greatly assist in writing solid C code in GCC. I am by no means a professional in logic or verifiable C, so I might be misguided in thinking that verifiable C will help, but I just want advice from people more experienced with GCC than me. Thanks in advance for your responses.


r/gcc • • Aug 10 '26

GNU Tools Weekly News Week 50 (August 9, 2026)

7 Upvotes

Release updates for GNU toolchain:
 * GCC 16.2.0 was released!
  * https://inbox.sourceware.org/gcc/r8p34qp8-r1qq-9nn3-r499-1q833r6801n4@fhfr.qr/
  * status: https://inbox.sourceware.org/gcc/3s8pqo7q-s5qp-21r1-6qpo-6n8srp3rpsn4@fhfr.qr/
 * GCC 14.5.0 is planed to be released on Sep 11th (RC1 on Sep 4th)
  * https://inbox.sourceware.org/gcc/anWnjIo15_2FrBEf@tucnak/
 * GDB 18 release branch was created
  * https://inbox.sourceware.org/gdb/announce.6a74bc19.18b7d65e.395d2.50a7@mx.google.com/
  * with a prelease was created
   * https://inbox.sourceware.org/gdb-patches/6a74ce98.f1a44df3.162c5d.ceef@mx.google.com/
 *

GNU toolchain conference reminders:
 * GNU Tools Cauldron 2026, Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
   * cfp closes August 31st
  * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
* https://lpc.events/event/20/abstracts/

General/big GNU toolchain news:
 * Michael Meissner appointed PowerPC port co-maintainer (GCC)
  * https://inbox.sourceware.org/gcc/CADzB+2=8CJoq4g=tDA14mUcMs4B6wEwPUM6Rjkbv+vx+058_zQ@mail.gmail.com/
 * Surya Kumari Jangala appointed PowerPC reviewer (GCC)
  * https://inbox.sourceware.org/gcc/CADzB+2mLbJR7XhmS46YQD0DCXxjV8qJNF3DdcX3ZJ29Ny0wtCA@mail.gmail.com/
 * Pierre-Emmanuel Patry appointed Rust Front End maintainer (GCC)
  * https://inbox.sourceware.org/gcc/CAGWvnymaTEBMLw2o6N=oeSk_aQVs=wtsffS5gaVsouL5Ar9XLw@mail.gmail.com/

GCC easy issue to tackle of the week:
 * a/b -> 1 if it is known that `a==b` in VRP without DOM
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126745
  * this is a non-match one but the patch for this one should be
around 5-6 lines for the new method that gets added
  *  Reach out to Andrea Pinski <[andrew.pinski@oss.qualcomm.com](mailto:andrew.pinski@oss.qualcomm.com)> for
mentoring on this issue.
 * Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

GCC commits:
 * https://gcc.gnu.org/r17-2890 ... r17-3172 283 commits
 * frange - sub-ranges
  * https://gcc.gnu.org/r17-2891 https://gcc.gnu.org/r17-2892
https://gcc.gnu.org/r17-2898
  * https://gcc.gnu.org/r17-2928 https://gcc.gnu.org/r17-2929
https://gcc.gnu.org/r17-3038
  * https://gcc.gnu.org/r17-3041 https://gcc.gnu.org/r17-3042
https://gcc.gnu.org/r17-3043
  * https://gcc.gnu.org/r17-3055 https://gcc.gnu.org/r17-3147
https://gcc.gnu.org/r17-3148
  * https://gcc.gnu.org/r17-3162 https://gcc.gnu.org/r17-3163
 * match: Simplify `(A | C) == A` to `(A & C) != 0` when C is power of 2
  * https://gcc.gnu.org/r17-2916-g372d44c5611ecc
  * Week 27th easy issue of the week
 * scheduler compile time improvements
  * https://gcc.gnu.org/r17-2919 ... r17-2922
 * phiopt: Add some TARGET_MEM_REF support to factoring of loads
  * https://gcc.gnu.org/r17-2955-g1a751916c6d506
 * expand: Split divisions with near-power-of-two divisors
  * https://gcc.gnu.org/r17-2970-g298071eb7e88b0
 * Fix --enable-gather-detailed-mem-stats for PCH
  * https://gcc.gnu.org/r17-2968-g60623805437fc7
  * Oldest bug fixed for GCC 17 so far
 * match: Recognize add/sub absolute-value idiom
  * https://gcc.gnu.org/r17-2972-g36990bb0d14c48
  * 10+ year old bug
 * RISC-V: Implement reassociation width hook
  * https://gcc.gnu.org/r17-3000-ge0e794b089a127
 * Implement C++29 P3733R1 - More named universal character escapes
  * https://gcc.gnu.org/r17-3022-g72c343684eb8d2
 * GCC rs merge
  * 78 commits
  * https://gcc.gnu.org/r17-3059 ... https://gcc.gnu.org/r17-3136
 * OpenMP: Use VOID_TYPE_P to check for void return type in SIMD
function clones.
  * Week 44 easy issue
  * https://gcc.gnu.org/r17-3156-ge212f5ef86f1a8
 * gimplefe: Add support for REF_REVERSE_STORAGE_ORDER on mem
  * https://gcc.gnu.org/r17-3169-gfbdabd5f9a27c8
 * Improve tree_expr_nonnegative_p by using the ranger
  * https://gcc.gnu.org/r17-3171-g5af52562e3fb59

GCC discussion:
 * Changes in emails sent by the forge
  * https://inbox.sourceware.org/gcc/d21bf3f0-38f5-42fe-9ffe-79ac1bf62565@arm.com/
 * Proposed synchronisation of forge accounts with MAINTAINERS.yml
  * https://inbox.sourceware.org/gcc/010c2e55-7f21-4819-8657-f2ad9eccd616@foss.arm.com/

GCC bugzilla stats
 * 154 new issues filed
 *  88 issues closed

binutils/gdb commits:
 *
gdb discussion:
 *
binutils discussion:
 *
glibc commits:
 *
glibc discussion:
 * Hurd and trust relationship with file system translators
  * https://inbox.sourceware.org/libc-alpha/87tsp528bj.fsf@oldenburg.str.redhat.com/


r/gcc • • Aug 03 '26

GNU Tools Weekly News Week 49 (August 2, 2026)

5 Upvotes

Release updates for GNU toolchain:
 * GCC 16.2.0 RC1 was done
  * https://inbox.sourceware.org/gcc/amxz3rGMpTljcyvm@tucnak/
  * Status
   * https://inbox.sourceware.org/gcc/amx74xvrAdSiIIEF@tucnak/

GNU toolchain conference reminders:
 * GNU Tools Cauldron 2026, Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
 * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
  * https://lpc.events/event/20/abstracts/

General/big GNU toolchain news:
 * GCC SC approved AI/LLM policy
  * https://inbox.sourceware.org/gcc/CAGWvny=KZcazorvmCU3gdT4dBcMJm6S_769Ne+aTfbO_nZ_HsQ@mail.gmail.com/
  * https://gcc.gnu.org/ai-policy.html
  * **Please read it before asking any questions about the policy**
  * Many news articles about the adoption (not posting them)
 * Progress toward compiling Linux with gccrs
  * https://lwn.net/Articles/1083202/
  * Currently subscriber-only (week only)
 * Maciej W. Rozycki was appointed as binutils global maintainer
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=4b8269718f60378f880ea83d061c7338783bbdb3
  * https://inbox.sourceware.org/binutils/alpine.DEB.2.21.2607272357300.14485@angie.orcam.me.uk/

GCC easy issue to tackle of the week:
(sorry about last week's being about an invalid transformation)
 * (si)~(ui)si_var
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126523
  * Reach out to Andrea Pinski <[andrew.pinski@oss.qualcomm.com](mailto:andrew.pinski@oss.qualcomm.com)> for
mentoring on this issue.
 * Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

GCC commits:
 * https://gcc.gnu.org/r17-2721 r17-2889 169 commits
 * aarch64: Add Support for SVE2p3/SME2p3 dot product intrinsics
  * https://gcc.gnu.org/r17-2751-g2a64a564f5eeb5
 * aarch64: Add Support for F16F32DOT
  * https://gcc.gnu.org/r17-2754-g4811e4c9836e52
 * aarch64: Add support for sve2p3 and sme2p3 conversion intrinsics
  * https://gcc.gnu.org/r17-2755-g7695a61179f48f
 *  MATCH: fold signbit comparison and conditional negate to copysign
  * https://gcc.gnu.org/r17-2823-g1c8ca0108746d3
  * Easy issue week 38
 * MATCH: Simplify zero/sign extension bit operations
  * https://gcc.gnu.org/r17-2824-gece564fdaa15a0
 * RISC-V: Add intrinsic support for Zvabd
  * https://gcc.gnu.org/r17-2821-g6df026ea07b0cf
 * MATCH: Simplify min of clz/ctz to clz/ctz of bitwise or
  * https://gcc.gnu.org/r17-2815-g1743c12e3512bf
 * frange improvements
  * https://gcc.gnu.org/r17-2829 https://gcc.gnu.org/r17-2828
https://gcc.gnu.org/r17-2827
  * https://gcc.gnu.org/r17-2806 https://gcc.gnu.org/r17-2764
https://gcc.gnu.org/r17-2758

GCC discussion:
 * See above about AI policy

GCC bugzilla stats
 * 184 new issues filed
 *  62 issues closed

binutils/gdb commits:
 *
gdb discussion:
  *
binutils discussion:
 *
glibc commits:
 *
glibc discussion:
 * Suggestion: Changes to release process, release from branch
  * https://inbox.sourceware.org/libc-alpha/PAWPR08MB89826DDF3C534485790AFFA983CC2@PAWPR08MB8982.eurprd08.prod.outlook.com/
 * Unfortunate interaction of glibc-2.44 and gnulib regarding
posix_spawn_file_actions_addchdir => infinite recursion
  * https://inbox.sourceware.org/libc-alpha/7eb0b5186e742958095a8e6c0ba28973412ab1f1.camel@xry111.site/


r/gcc • • Jul 29 '26

GCC AI Policy Announcement

Thumbnail gcc.gnu.org
20 Upvotes

r/gcc • • Jul 27 '26

GNU Tools Weekly News Week 48 (July 26, 2026)

6 Upvotes

Release updates for GNU toolchain:
 * glibc 2.44 was released
  * https://inbox.sourceware.org/libc-alpha/teaVXxrfQH2qv0xBul7sXg@gentoo.org/
 * binutils 2.47 was released
  * https://inbox.sourceware.org/binutils/87o6fty5pz.fsf@redhat.com/

GNU toolchain conference reminders:
 * GNU Tools Cauldron 2026, Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
 * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
  * https://lpc.events/event/20/abstracts/
  * Note the CFP deadline has past:
   * https://inbox.sourceware.org/gcc/875x24wsik.fsf@gnu.org/T/#u

General/big GNU toolchain news (including sourceware news):
 * sourceware.org is now using nginx as the proxy (TLS terminator) in
front of apache (httpd) to help the load with AI bots
  * https://inbox.sourceware.org/gcc/20260725221825.GU13327@gnu.wildebeest.org/T/
  * AI bots have gotten really aggressive lately and started to abuse
residential proxies (via smart appliances)
   * See https://lwn.net/Articles/1080822/ and other articles about this
   * https://krebsonsecurity.com/2026/07/lg-to-ban-residential-proxies-from-smart-tv-apps/
  * sourceware.org worked with the developer of anubis
(https://github.com/TecharoHQ/anubis/) for a release with improved
support here

GCC easy issue to tackle of the week:
 * `smax <smin <a, nonneg>, 0>` can be simplified into `umin<a, nonneg>` (RTL)
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125757
  * this is a RTL one this week
  * Reach out to Andrea Pinski <[andrew.pinski@oss.qualcomm.com](mailto:andrew.pinski@oss.qualcomm.com)> for
mentoring on this issue.
 * Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

 GCC commits:
 * https://gcc.gnu.org/r17-2532 ... r17-2720 189 commits
 * RISCV: Improving atomic sequences
  * https://gcc.gnu.org/r17-2556-gb6bebf2a7326e6
 * bpf: Improve rtl costs
  * https://gcc.gnu.org/r17-2570-gc743ce6b75543f ... r17-2572-g3c71ff89bb0315
 * AArch64: use ranger to fold WHILE_ULT to ptrue
  * enable ranger in isel
   * https://gcc.gnu.org/r17-2600-g888b4d45e854d2
  * https://gcc.gnu.org/r17-2601-g89c55025122c0a .. r17-2602-gfe724b27ce6dad
 * match: Fold constant conditional selects
  * https://gcc.gnu.org/r17-2604-g3e2b0fcab75527
 * frange: Improvements
  * https://gcc.gnu.org/r17-2631-gd284bf3a1349c1
  * https://gcc.gnu.org/r17-2645-g93a9ff5383a253
 * phiopt: for non-diamond case, invoke a limited conditional store elimination
  * https://gcc.gnu.org/r17-2635-geb8011467d0ce7
  * https://gcc.gnu.org/r17-2634-gfd3e590360dc4f
 * match: Fold averages with equal operands
  * https://gcc.gnu.org/r17-2670-g3b126071b10e5b
 * tree-optimization: Fix strlen(s) != 0 not folded into *s [PR92408]
  * https://gcc.gnu.org/r17-2695-g1649ee187dfdb8
  * Easy issue of the week: Week 43
 * Improving floating point comparison combine with trapping math
  * https://gcc.gnu.org/r17-2707-g7d781db9c3d515
  * https://gcc.gnu.org/r17-2708-gea33efbbdcf697
  * https://gcc.gnu.org/r17-2709-gde8be0eb05d951

GCC discussion:
 * RFC: C preprocessor extension: Multiline/block macro definition
  * https://inbox.sourceware.org/gcc/CALzUo856qtVxh8PobEG7Qkf8pp3JkxCeunx7ASbDkmKSeifxbg@mail.gmail.com/

GCC bugzilla stats
 *  104 new issues filed
 *  50 issues closed

binutils/gdb commits:
 *
gdb discussion:
 *
binutils discussion:
 *

glibc commits:
 *
glibc discussion:
 * The state of the architectures
  * https://inbox.sourceware.org/libc-alpha/3V0xKX0yTuebq-SW7D-ZLg@gentoo.org/


r/gcc • • Jul 26 '26

GNU Binutils 2.47 Released

7 Upvotes

Control whether relocations referencing local binding symbols are adjusted to use section symbols.

RISC-V extensions.

BFD linker -O 0 to inhibit combining mergeable sections.

https://lists.gnu.org/archive/html/info-gnu/2026-07/msg00006.html


r/gcc • • Jul 25 '26

The GNU C Library version 2.44 is now available!

13 Upvotes

New features include system-wide tunables, memory mapping optimization using transparent huge pages, more optimized and correctly rounded mathematical functions, vectorization for AArch64 and RISC-V, Guarded Control Stack locking on AArch64, support for LoongArch32, and more...


r/gcc • • Jul 21 '26

GNU Tools Weekly News Week 47 (July 19, 2026)

5 Upvotes

Release updates for GNU toolchain:
* GDB 18 release schedule proposal
* https://inbox.sourceware.org/gdb-patches/87fr1gcb4p.fsf@redhat.com/

GNU toolchain conference reminders:
* GNU Tools Cauldron 2026, Fri-Sun, October 2-4 (Prague, Czechia)
* https://gcc.gnu.org/wiki/cauldron2026
* https://conf.gnu-tools-cauldron.org/prg26/cfp
* Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
* https://lpc.events/event/20/abstracts/

General/big GNU toolchain news (including sourceware news):
* Meeting Minutes - Office Hours for the GNU Toolchain - 2026-07-16
* https://inbox.sourceware.org/gcc/43420f3d-9e50-4f50-9553-034af94438f4@redhat.com/

GCC easy issue to tackle of the week:
* None this week, Andrea is on vacation.

GCC commits:
* https://gcc.gnu.org/r17-2346 ... r17-2531 186 commits
* cse: Eliminate redundant scalar duplication at different vector widths
* https://gcc.gnu.org/r17-2354-g10f6223d833874
* C++29: P3424R2: Deallocations with Throwing Exception Specification
Are Ill-formed
* https://gcc.gnu.org/r17-2482-g57ecb9897a0964
* match: Simplify sign tests for MIN and BIT_IOR
* https://gcc.gnu.org/r17-2487-gf8eb22d8408b25
* Easy issue of the week: Week 45
* lto: Support #pragma GCC diagnostic
* https://gcc.gnu.org/r17-2493-g4c85f7cf587f0f .. r17-2488-ga7db48e71b9483
* aarch64: deprecate the TME extension
* https://gcc.gnu.org/r17-2498-g17f084306c68c4
* riscv: Add min support for some extensions
* Svrsw60t59b, Ssqosid, Ssctr, Smctr, Smcdeleg, Ssccfg
* Ziccamoc, Ziccid
* https://gcc.gnu.org/r17-2521-ga3ee6072ca6d72 ... r17-2528-g741dd3fa641a45
* Improve BB vectorization of reductions
* https://gcc.gnu.org/r17-2478-g3adb3325954177

GCC discussion:
* [RFC] Proposal for tagged_by attribute to describe union discriminators
* https://inbox.sourceware.org/gcc/alf4-IVENZDyJ70X@thesun/

GCC bugzilla stats
* 91 new issues filed
* 58 issues closed

binutils/gdb commits:
* gdb: add annotation in 'info locals' command for variables shadowing case
* https://sourceware.org/cgit/binutils-gdb/commit/?id=2465b9e4131514bdb42365076ef65ef6ad0e3f6c

gdb discussion:
* [RFC] [gdb] Move ChangeLog files to archive dir
* https://inbox.sourceware.org/gdb-patches/20260620114010.2417788-1-tdevries@suse.de/
binutils discussion:
*

glibc commits:
* math: Update tanh from CORE-MATH (revision cf237fa0)
* https://sourceware.org/cgit/glibc/commit/?id=6b29e74c731e2ac1bc8048a389fdaf029bd96072
glibc discussion:
*


r/gcc • • Jul 13 '26

[C] Will the compiler reorder user-written assembly instructions?

9 Upvotes

I need to write a function with void function() "fingerprint" whose body is a sequence of "advanced assembly code" like this:

asm volatile ( "store reg1, %0(sp)" :: "i"(__builtin_offsetof(mytype, reg1)));

I compile it with -O3 -fomit-frame-pointer and can see that in the emitted code there is neither a C prologue not epilogue for the stack management, just like I want.

My question revolves around the possibility that the optimizer could reorder those asm volatile instructions: this is something I would like not to happen.

Is this possible at all?
If so, is there a way to avoid it?

[UPDATE]: Possibly working workaround here.


r/gcc • • Jul 13 '26

GNU Tools Weekly News Week 46 (July 12, 2026)

8 Upvotes

Release updates for GNU toolchain:
 * dwz 0.17 was released July 11th
  * https://inbox.sourceware.org/gcc/20260711201828.GF31804@gnu.wildebeest.org/T/#u
 * binutils 2.47 release branch was created
  * https://inbox.sourceware.org/binutils/CAMe9rOrBj1z8EA3FA9VfVMNkMbNCtoYfGfWiGSCjht=8bUHoTw@mail.gmail.com/T/#m541bfed9931e78a42f7a582f1e2c9585059a6fc2

GNU toolchain conference reminders:
 * GNU Tools Cauldron 2026, Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
 * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
  * https://lpc.events/event/20/abstracts/

General/big GNU toolchain news (including sourceware news):
 * Proposed updates to the gcc forge repositories
  * https://inbox.sourceware.org/gcc/ca51039e-cb61-430e-979a-f5948c3edb4f@arm.com/
 * GCC MAINTAINERS file is now generated
  * https://inbox.sourceware.org/gcc/92341a31-aecc-4261-bc8c-f3077fe31c1d@arm.com/

GCC easy issue to tackle of the week:
 * None this week, Andrea is on vacation.

GCC commits:
 * https://gcc.gnu.org/r17-2148 -  r17-2345  198 commits
 * libbacktrace: support returning discriminator field
  * https://gcc.gnu.org/r17-2177-g49a5c52438b6a8
 * aarch64: Add support for -mcpu=rigel
  * https://gcc.gnu.org/r17-2197-g2f7613d36fecb6
 * gccrs merge
  * https://gcc.gnu.org/r17-2223 - r17-2260
 * s390: Remove -m31 support
  * https://gcc.gnu.org/r17-2272-g035f177a1eab31
 * fold-mem-offsets: Convert from DF to RTL-SSA
  * https://gcc.gnu.org/r17-2301-gf7a75a1506d91f
 * match: Improved comparison of integers to FP constants.
  * https://gcc.gnu.org/r17-2324-g081959973e38fd
 * expmed: Optimize 32-bit unsigned division by constants on 64-bit targets
  * https://gcc.gnu.org/r17-2334-gc585baad310a4a

GCC discussion:
 * Draft C2Y _BitInt related proposals
  * https://inbox.sourceware.org/gcc/ak0RdTxEebAf4T6K@tucnak/

GCC bugzilla stats
 *  105 new issues filed
 *  55 issues closed

binutils/gdb commits:
 * aarch64: Add support for FEAT_SME_FA64
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=d708c86adccb169dd8bf5c7f4d73d7cab238d965
 *

gdb discussion:
 *
 binutils discussion:
 *

 glibc commits:
 * riscv: Add RVV stpncpy and strncpy for both multiarch and
non-multiarch builds
  * https://sourceware.org/cgit/glibc/commit/?id=df0669d41d753269312374e2eb6bd107bbec9c7b
  * https://sourceware.org/cgit/glibc/commit/?id=59cb960a22fbacb8b8baaa049529bf4638dfc625
 * Revert "malloc: aarch64: Add ifuncs for malloc functions"
  * https://sourceware.org/cgit/glibc/commit/?id=d70dd7d72273ac1aa53b435156de3f50f0c5a868

glibc discussion:

*


r/gcc • • Jul 07 '26

GNU Tools Weekly News Week 45 (July 5, 2026)

5 Upvotes

Release updates for GNU toolchain:
 * GCC 16.2.0 first week in August
  * https://inbox.sourceware.org/gcc/664sq11r-5665-71rs-9p94-9s6166660r68@fhfr.qr/
 *  glibc-2.44 release: Soft freeze
  * Hard freeze July 4th
  * https://inbox.sourceware.org/libc-alpha/5439103.jY9Djz4Zq0@noumea/

GNU toolchain conference reminders:
 * GNU Tools Cauldron 2026, Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
 * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
  * https://lpc.events/event/20/abstracts/

General/big GNU toolchain news (including sourceware news):
 * GCC AI Policy Working Group submitted a proposed policy to the SC (July 3rd)
  * https://gcc.gnu.org/wiki/working-group-ai-policy
 * Rustc GCC backend report
  * https://blog.antoyo.xyz/rustc_codegen_gcc-progress-report-42
 * smtgcc mid-year update
  * https://inbox.sourceware.org/gcc/Pine.NEB.4.64.2607011339410.4763@gateway.kwa/
 * Talk by Avinal Kumar on glibc's charset/conversion subsystems:
"Lost in translation"
  * https://avinal.space/talks/devconf-2026/#/1

GCC easy issue to tackle of the week:
 * `MIN<nonnegative,a> >= 0` is not simplified into `a >= 0`
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126087
  * Reach out to Andrea Pinski <[andrew.pinski@oss.qualcomm.com](mailto:andrew.pinski@oss.qualcomm.com)> for
mentoring on this issue.
 * Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

GCC commits:
 * https://gcc.gnu.org/r17-1944 .. r17-2147  204 commits
 * Ada update (Thanks again Marc):
  * https://gcc.gnu.org/r17-1956-gd54ca4e4da5db3 ... r17-1971-gb2029c82ff9174
  * Bug fixes.
  * Android support enhancement.
  * Flare OOP "Attribute Subprogram" first implementation.
  * Diagnostic messages improvements.
 * Match: Support unsigned scalar SAT_MUL form 14
  * https://gcc.gnu.org/r17-1946-g95540e74f33dad
 * aarch64: Fix tls debuginfo missing location info
  * https://gcc.gnu.org/r17-2093-g97d9016b230cca
 * libstdc++: implement LWG3662 basic_string::append/assign(NTBS, pos,
n) suboptimal
  * https://gcc.gnu.org/r17-2095-g7084db3f6e1cc6
 * SH: Switch to LRA permanently
  * https://gcc.gnu.org/r17-2104-g75a75f22f3a33e
 * cdcde: fold memset with length in [0, 1] to conditional store
  * https://gcc.gnu.org/r17-2113-ga8072f31bc9000
 * c++: Implement C++29 P2953R5 - Adding restrictions to defaulted
assignment operator functions
  * https://gcc.gnu.org/r17-2127-gc1a7d0a2140563
 * recognize CLZ via isolated MSB DeBruijn lookup
  * https://gcc.gnu.org/r17-2131-ga20f4528f3ab84
 * aarch64: Port NEON intrinsics to pragma-based framework
  * https://gcc.gnu.org/r17-2018-gefbc7fbb70d875 ... r17-2023-gde97b51852881d
 * c++: Implement C++29 P3540R3 - #embed offset parameter
  * https://gcc.gnu.org/r17-1995-g1ec0c5428cf84e
 * RISC-V: Add basic spacemit-x100 and Spacemit-A100 core support
  * https://gcc.gnu.org/r17-1983-g8596c662854b86
  * https://gcc.gnu.org/r17-2012-ge71bc0f8d7f93c

GCC discussion:
 * [RFC] Turning off trapping-math for C and C++ front-ends by default
  * https://inbox.sourceware.org/gcc/CALvbMcA6P_q7WNm1KOopzxhzRJHFi9T9_STaCtZrm1ZA-0nNtQ@mail.gmail.com/

GCC bugzilla stats
 *  97 new issues filed
 *  65 issues closed

binutils/gdb commits:
 * RISC-V: Add Zvdota extension classes
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=89d59bf712045252b527bdfb69c07b0a29db7007
 * RISC-V: Add Zvbdota extension support
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=794f538c3e57e3f55a6224a7206fdb0ea7815a82

gdb discussion:
 *
binutils discussion:
 *

glibc commits:
 * Add system-wide tunables
  * https://www.phoronix.com/news/Glibc-System-Tunables
  * https://sourceware.org/cgit/glibc/log/?id=e24269f74b8cd37ce33652e752f8012c3bfcdadc&qt=range&q=e24269f74b8cd37ce33652e752f8012c3bfcdadc...fae194043a099d45c044c883467c934153ecc51f
  * https://inbox.sourceware.org/libc-alpha/cover.1782444639.git.dj@redhat.com/

glibc discussion:
 * x86-64 TCB layout dependency in Chrome, Firefox still not fixed
  * https://inbox.sourceware.org/libc-alpha/lhucxx5oo4n.fsf@oldenburg.str.redhat.com/
 * The libc-locales mailing list is going to be closed, please use libc-alpha
  * https://inbox.sourceware.org/libc-alpha/351127e3-0397-438c-8730-3ef35605bdb9@redhat.com/


r/gcc • • Jun 29 '26

GNU Tools Weekly News Week 44 (June 28, 2026)

6 Upvotes

Release updates for GNU toolchain:
 * GCC 14.4.0 was released
  * https://inbox.sourceware.org/gcc/aj5L4BbnW8XMF7GQ@tucnak/

GNU toolchain conference reminders:
 * GNU Tools Cauldron 2026, Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
 * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
  * https://lpc.events/event/20/abstracts/

GCC easy issue to tackle of the week (2 this week):
 * ICE with return type of typedef of void and `#pragma omp declare simd`
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111856
  * Reach out to Andrea Pinski <[andrew.pinski@oss.qualcomm.com](mailto:andrew.pinski@oss.qualcomm.com)> for
mentoring on this issue.
 * For RISC-V, prefer li+slli rather than lui+add for some constants
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126022
  * Reach out to Jeff Law <[jeffrey.law@oss.qualcomm.com](mailto:jeffrey.law@oss.qualcomm.com)> for mentoring
on this issue.
 * Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

GCC commits:
 * https://gcc.gnu.org/r17-1733 ...  r17-1943  211 commits
 * RTL: add dependent filter handling
  * https://gcc.gnu.org/r17-1779-g9d82914d073e2e ...
https://gcc.gnu.org/r17-1783-gc23f20c10d89af
  * https://inbox.sourceware.org/gcc-patches/20260526142247.172296-1-rdapp.gcc@gmail.com/
 * AArch64/SVE: Optimize vec_init for partial SVE vector modes
  * https://gcc.gnu.org/r17-1799-gb3acc5dd98f44d
 * rs6000: Add Future Vector Integer Arithmetic Instructions
  * https://gcc.gnu.org/r17-1800-ga3b8e252101ada
 * OMP improvements
  * De-duplicate libgomp entry points for OMPT
  * https://inbox.sourceware.org/gcc-patches/20260622165754.226314-1-parras@baylibre.com/
  * https://gcc.gnu.org/r17-1803-g37c96bf08325bf ...
https://gcc.gnu.org/r17-1806-gd50e9f17fffa9b
 * rs6000: Builtins for ECC cryptography instructions
  * https://gcc.gnu.org/r17-1856-g2b3c882b5b8e96
 * RISC-V: GLIBC's setjmp preserves callee-saved registers
  * https://gcc.gnu.org/r17-1857-g21dad398994ff5
 * GCC rust sync
  * https://gcc.gnu.org/r17-1863-g5333e241a36912 ...
https://gcc.gnu.org/r17-1904-g30a64527c56af9
 * match: Use ranges for int-float comparisons
  * https://gcc.gnu.org/r17-1931-g8351875a5e2c52
 * Use tree_expr_nonnegative_p instead of TYPE_UNSIGNED for MAX (A, B)
(==,!=) 0 -> (A|B) (==,!=) 0
  * https://gcc.gnu.org/r17-1938-g61b702d88c8e55
 * Remove BOOL_BITFIELD define from system.h and update its uses
 * https://gcc.gnu.org/r17-1943-g08944b70002610

GCC discussion:
 * [RFC TREE-WIDE] gcc: stop using 'int' to represent sets of qualifiers
  * https://inbox.sourceware.org/gcc/20260626191622.1785567-1-aarsenovic@baylibre.com/
 * RFC: Allow "(mem:<vectype> (reg:<vectype>))"
  * https://inbox.sourceware.org/gcc/82bf28f3-5543-4925-98d9-5ddf7dc23855@baylibre.com/
 * [RFC] LRA: Carrying hard registers around
  * https://inbox.sourceware.org/gcc/ajuBckDkxUIVXvyu@li-819a89cc-2401-11b2-a85c-cca1ce6aa768.ibm.com/
 * RFC: Bump minimum GNU Make version to 3.81
  * https://inbox.sourceware.org/gcc/CAH6eHdRuOhrEEYp6jmGZgq6QXUsMe4kr66LY62uk59MpYnTauw@mail.gmail.com/
 * [RFC] Add simple forwprop across edges (PHIs)
  * https://inbox.sourceware.org/gcc-patches/20260625233902.2605630-1-andrew.pinski@oss.qualcomm.com/

GCC bugzilla stats
 *  101 new issues filed
 *  76 issues closed

binutils/gdb commits:
 * binutils: RISC-V: Add some extensions
  * Zalasr
  * SpacemiT vendor extension xsmtvdot
  * SpacemiT vendor extension xsmtvdotii
  * Svrsw60t59b
  * Zvabd
  * https://sourceware.org/cgit/binutils-gdb/log/?qt=range&q=d3b84dac949ac10f8736c85253b4a1073d244ac1...d26861e53c74d54be86149dd5b78d339487bebb4
  * Smpmpmt
   * https://sourceware.org/cgit/binutils-gdb/commit/?id=e56bd09181016800870de47c1f3a1091f71d9120
 * gdb: Handle nested Ada functions with gnat-llvm
  * https://sourceware.org/cgit/binutils-gdb/commit/?id=26d17a9b24dfd4a3894bc19ac752466ea10e80b2
 *

gdb discussion:
 * Adding architecture-specific commands in GDB
  * https://inbox.sourceware.org/gdb/077b9f00-ec84-440f-a84a-d804815aa77e@arm.com/

binutils discussion:
 *

glibc commits:
 * manual: Document indirect functions (IFUNC)
  * https://sourceware.org/cgit/glibc/commit/?id=657fe73fb1ce09c109fffafb16d565eedbbe05ed

glibc discussion:
 *


r/gcc • • Jun 26 '26

GCC 14.4 Released

Thumbnail gcc.gnu.org
16 Upvotes

104 fixes!


r/gcc • • Jun 22 '26

GNU Tools Weekly News Week 43 (June 21, 2026)

3 Upvotes

Release updates for GNU toolchain:
 * GCC 14 branch is frozen for GCC 14.4.0 release
  * https://inbox.sourceware.org/gcc/7qp3n3rq-3935-0qnn-s4s9-425230sso679@fhfr.qr/
 * GCC 14.4.0 RC1 is done
  * https://inbox.sourceware.org/gcc/864p303q-o5n8-s3q4-9901-24o31420p21s@fhfr.qr/

GNU toolchain conference reminders:
 * GNU Tools Cauldron 2026, Fri-Sun, October 2-4 (Prague, Czechia)
  * https://gcc.gnu.org/wiki/cauldron2026
  * https://conf.gnu-tools-cauldron.org/prg26/cfp
 * Toolchains Track at LPC 2026, October 7th (Prague, Czechia)
  * https://inbox.sourceware.org/gcc/CAKwvOdkaE7nHQbMRKBHmY6jE326bx=czi8yeL2qypsOj3Pq+Og@mail.gmail.com/
  * https://lpc.events/event/20/abstracts/

General/big GNU toolchain news:
 * Acceptance of GCC WebAssembly Backend
  * https://inbox.sourceware.org/gcc/CAGWvny=AE17wQU5mfz8UGWybVBSsb_ffqHcthS78g8zdzK6xSw@mail.gmail.com/
 * Joel Brobecker is stepping down as a gdb release manager
  * https://inbox.sourceware.org/gdb-patches/536dc95f-540f-4a1a-9ccc-73b34eb50819@simark.ca/T/

GCC easy issue to tackle of the week:
 * strlen(s) != 0 not folded into *s (when separate statements)
  * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92408
  * Reach out to Andrea Pinski <[andrew.pinski@oss.qualcomm.com](mailto:andrew.pinski@oss.qualcomm.com)> for
mentoring on this issue.
 * Previous ones are listed on https://gcc.gnu.org/wiki/EasyIssuesOfTheWeek

GCC commits:
 * https://gcc.gnu.org/r17-1560 ... r17-1732  173 commits
 * Ada updates (Thanks Marc)
  * Bug fixes.
  * Diagnostics improvements.
  * Constructor Flare extension adjustments.
  * https://gcc.gnu.org/r17-1633-g881cb10e96d875 ...
https://gcc.gnu.org/r17-1653-g52f6d044261933
  * https://gcc.gnu.org/r17-1688-g343265c50f930c ...
https://gcc.gnu.org/r17-1701-g3b0af59dc9e67f
 * match.pd: Recognize integer spaceship operator patterns
  * https://gcc.gnu.org/r17-1582-g7659926b80deaf
 * c++, libcpp: Add -std=c++2[9d] and -std=gnu++2[9d] options
  * https://gcc.gnu.org/r17-1595-g0c5c6249a2e9a7
 * prange was improved and is in use
  * https://gcc.gnu.org/r17-1601-g8b45cd81fc3509 ...
https://gcc.gnu.org/r17-1604-gca582ee36820a3
 * Add vec_deconstruct costing kind
  * https://gcc.gnu.org/r17-1655-g7d351b07e5b85c
 * match: mask/sub sign-extension idiom not canonicalized to sign extension
  * https://gcc.gnu.org/r17-1680-gc05164c348242b
 * match: Optimize bit_ior/bit_and {bit_not} rshift to min/max
  * https://gcc.gnu.org/r17-1683-g43356828d897ad
 * PHIOPT (ifcvt): load commonization/factoring
  * https://gcc.gnu.org/r17-1703-g3c0fd2976ab4f4 ...
https://gcc.gnu.org/r17-1705-gcf64e6b0e07355
 * Match: Support unsigned scalar SAT_MUL form 13
  * https://gcc.gnu.org/r17-1730-g971f8d5b5fd5ce ...
https://gcc.gnu.org/r17-1732-ga05799c29c50d7

GCC discussion:
 *

GCC bugzilla stats
 *  128 new issues filed
 *  91 issues closed

binutils/gdb commits:
 *

gdb discussion:
 *

binutils discussion:
 *

glibc commits:
 * riscv: Add RVV memmove for both multiarch and non-multiarch builds
  * https://sourceware.org/cgit/glibc/commit/?id=60f7247847ba7244541fc783079c298416756399

glibc discussion:
 *