GNU
gcc.gnu.org › gcc-15
GCC 15 Release Series - GNU Project
1 week ago - The GCC developers are pleased to announce the release of GCC 15.3.
GNU
gcc.gnu.org › gcc-15 › changes.html
GCC 15 Release Series — Changes, New Features, and Fixes - GNU Project
April 13, 2026 - This page is a "brief" summary of some of the huge number of improvements in GCC 15.
GCC 15 Released 🎉
AMD GPU (GCN) The standard C++ library (libstdc++) is now supported and enabled. I've really got to give GCC's GPU offloading a try sometime. Does anyone have any experience with the performance of this, vs reasonably well written GPU code by hand? I might do some tests and write them up to see if its actually workable for high performance code Experimental support for supporting generic devices has been added; specifying gfx9-generic, gfx10-3-generic, or gfx11-generic to -march= will generate code that can run on all devices of a series. Additionally, the following specific devices are now have experimental support, all of which are compatible with a listed generic: gfx902, gfx904, gfx909, gfx1031, gfx1032, gfx1033, gfx1034, gfx1035, gfx1101, gfx1102, gfx1150, and gfx1151. To use any of the listed new devices including the generic ones, GCC has to be configured to build the runtime library for the device. Note that generic support requires ROCm 6.4.0 (or newer). For details, consult GCC's installation notes. More on reddit.com
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April 25, 2025GCC, the GNU Compiler Collection 15.1 released
The new default is -std=gnu23, which means C23's breaking changes are now the default. In my experience so far the most disruptive has been old-style prototypes, particularly empty parameter lists. This: void f(); Now means: void f(void); Instead of "unspecified number of arguments." Projects depending on the old behavior include GDB, GMP, GNU Make, and Vim. These require special consideration when building with GCC 15. More on reddit.com
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April 25, 2025GNU
gcc.gnu.org › gcc-15 › porting_to.html
Porting to GCC 15 - GNU Project
GCC 15 changes the default language version for C compilation from -std=gnu17 to -std=gnu23. If your code relies on older versions of the C standard, you will need to either add -std= to your build flags, or port your code to C23.
Red Hat
developers.redhat.com › articles › 2025 › 04 › 24 › new-c-features-gcc-15
New C++ features in GCC 15 | Red Hat Developer
April 25, 2025 - The next major version of the GNU Compiler Collection (GCC), 15.1, is expected to be released in April or May 2025. Like every major GCC release, this version will bring many additions, improvements, bug fixes, and new features.
Reddit
reddit.com › r/cpp › gcc 15 released 🎉
r/cpp on Reddit: GCC 15 Released 🎉
April 25, 2025 -
🎉Congratulations to the GCC team!
🎆🎇🔥💥 🤩 🎊 🥳 🤟 🍻 🥂 👍
Release Notes
GNU Git Branch and Tag (quite slow)
Github mirror
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AMD GPU (GCN) The standard C++ library (libstdc++) is now supported and enabled. I've really got to give GCC's GPU offloading a try sometime. Does anyone have any experience with the performance of this, vs reasonably well written GPU code by hand? I might do some tests and write them up to see if its actually workable for high performance code Experimental support for supporting generic devices has been added; specifying gfx9-generic, gfx10-3-generic, or gfx11-generic to -march= will generate code that can run on all devices of a series. Additionally, the following specific devices are now have experimental support, all of which are compatible with a listed generic: gfx902, gfx904, gfx909, gfx1031, gfx1032, gfx1033, gfx1034, gfx1035, gfx1101, gfx1102, gfx1150, and gfx1151. To use any of the listed new devices including the generic ones, GCC has to be configured to build the runtime library for the device. Note that generic support requires ROCm 6.4.0 (or newer). For details, consult GCC's installation notes.
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Hurry up package managers I don’t want to build it myself.
Arm Developer
developer.arm.com › community › arm-community-blogs › b › tools-software-ides-blog › posts › gcc-15-continuously-improving
GCC 15: Continuously Improving
June 26, 2025 - In GCC 15 Arm, GCC Community, and our partners have continued innovating and improving code generation for Arm based platforms. GCC 15 continues the trend to support control flow vectorization, mixing SVE and Adv.
Phoronix
phoronix.com › news › GCC-15-Stage-1-Ends-November
GCC 15 "Stage 1" Feature Development Ending Next Month - Phoronix
Richard Biener of SUSE published a GCC 15.0.0 status report for outlining the current development state of the GCC 15 open-source compiler as it works its way toward the stable GCC 15.1 release in the early months of 2025.
Debian
packages.debian.org › sid › amd64 › gcc-15
Debian -- Details of package gcc-15 in sid
gcc-10-hppa64-linux-gnu · This is the GNU C compiler, a fairly portable optimizing compiler for C. dep: binutils (>= 2.39) GNU assembler, linker and binary utilities · dep: cpp-15 (= 15.2.0-15) GNU C preprocessor · dep: gcc-15-base (= 15.2.0-15) GCC, the GNU Compiler Collection (base package) ...
GNU
gnu.org › software › gcc › gcc-15
GCC 15 Release Series - GNU Project
August 8, 2025 - The GCC developers are pleased to announce the release of GCC 15.2.
Medium
medium.com › @xersendo › moving-to-c-26-how-to-build-and-set-up-gcc-15-1-on-ubuntu-f52cc9173fa0
Moving to C++26: How to Build and Set Up GCC 15.1 on Ubuntu
May 3, 2025 - GCC 15.1 is out with C++26 features! But Ubuntu still ships GCC 13. So let’s build 15.1 from source and start experimenting.
Medium
medium.com › @Re-News › gcc-15-a-major-leap-in-compiler-technology-with-c-23-avx10-2-and-enhanced-arm-support-109079c380af
GCC 15: A Major Leap in Compiler Technology with C++23, AVX10.2, and Enhanced ARM Support | by Re: News | Medium
April 25, 2025 - GCC 15 delivers major enhancements across languages and platforms, introducing a new COBOL front end, improved vectorization and incremental LTO, and expanded OpenMP 6.0 support, including unified memory on GPUs.
Intel
intel.com › content › www › us › en › developer › articles › technical › next-gen-performance-gcc-15.html
Next Generation Optimizations for GCC* 15
June 15, 2025 - In GCC 15, we made substantial advancements in O2 auto-vectorization, leading to notable performance improvements as evidenced by SPECrate* 2017 benchmarks. Furthermore, the -mtune=sierraforest architecture optimizations were meticulously refined, resulting in significant performance gains.
GNU
gcc.gnu.org › onlinedocs › 15.2.0
GCC 15.2 manuals - GNU Project
August 8, 2025 - GCC 15.2 Manual (also in PDF or PostScript or an HTML tarball)
Reddit
reddit.com › r/c_programming › gcc, the gnu compiler collection 15.1 released
r/C_Programming on Reddit: GCC, the GNU Compiler Collection 15.1 released
April 25, 2025 -
https://gcc.gnu.org/gcc-15/
Some discussion on hackernews: https://news.ycombinator.com/item?id=43792248
Awhile back, there was some discussion of code like this:
char a[3] = "123";
which results in a an array of 3 chars with no terminating NUL byte, and no warning from the compiler about this (was not able to find that discussion or I would have linked it). This new version of gcc does have a warning for that. https://gcc.gnu.org/pipermail/gcc-patches/2024-June/656014.html And that warning and attempts to fix code triggering it have caused a little bit of drama on the linux kernel mailing list: https://news.ycombinator.com/item?id=43790855
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The new default is -std=gnu23, which means C23's breaking changes are now the default. In my experience so far the most disruptive has been old-style prototypes, particularly empty parameter lists. This: void f(); Now means: void f(void); Instead of "unspecified number of arguments." Projects depending on the old behavior include GDB, GMP, GNU Make, and Vim. These require special consideration when building with GCC 15.
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IMO it's worth a warning, because it may indeed indicate a semantic error. It shouldn't be automatically fatal because it may not be an error, though that would be exceptional and deserves scrutiny to ensure its safety. If I read the tone of that second thread, there's contention about the default Makefile in one specific project making it fatal and thus highlighting a bunch of weak spots. Some people are grateful for the opportunity to fix it. Others will resent you for making them look bad.
GNU
gcc.gnu.org › pub › gcc › releases › gcc-15.2.0
Index of /pub/gcc/releases/gcc-15.2.0
Index of /pub/gcc/releases/gcc-15.2.0
GNU
gcc.gnu.org › pipermail › gcc-announce › 2025 › 000185.html
GCC 15.1 Released - GCC, the GNU Compiler Collection
April 25, 2025 - The GCC developers are proud to announce a new major GCC release, 15.1. The C frontend now defaults to the GNU C23 dialect. Some code needs porting for this, see https://gcc.gnu.org/gcc-15/porting_to.html#c23 for more details. Some remaining C23 features have been implemented, as well as some ...
LWN.net
lwn.net › Articles › 1018920
GCC 15.1 released [LWN.net]
April 25, 2025 - Version 15.1 of the GNU Compiler Collection has been released. Changes include implementing the C23 dialect by default, a number of new C++26 features, experimental support for unsigned integers in Fortran, a new COBOL front end, and more. See the GCC 15 changes page for details.
InfoWorld
infoworld.com › home › software development › programming languages › c language
GCC 15 compilers move toward completion | InfoWorld
March 17, 2025 - GCC (GNU Compiler Collection) 15 is moving forward as a planned update to the series, with a new front end for Cobol.
GNU
gcc.gnu.org › pipermail › gcc › 2025-April › 245971.html
GCC 15.1 Released - GNU.org
April 25, 2025 - The GCC developers are proud to announce a new major GCC release, 15.1. The C frontend now defaults to the GNU C23 dialect. Some code needs porting for this, see https://gcc.gnu.org/gcc-15/porting_to.html#c23 for more details. Some remaining C23 features have been implemented, as well as some ...