GCC 15.1 was officially released on April 25, 2025
Grigory Filatov
The GCC developers are pleased to announce the release of GCC 15.1.
This release is a major release, containing new features (as well as many other improvements) relative to GCC 14.x.
GCC 15.1 introduces several performance-related improvements across optimization strategies, diagnostics, and language-specific enhancements:
1. Enhanced Optimization Capabilities
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Loop vectorization improvements: -O2 now better handles loops with unknown trip counts, though still restricts vectorization when runtime checks for data dependencies/alignment are required1.
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New -flto-incremental option: Supports incremental Link-Time Optimization (LTO), potentially reducing rebuild times for large projects1.
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Prvalue optimization: Class prvalues used as function arguments are more aggressively constant-evaluated, improving code generation for temporary objects2.
2. Compile-Time Efficiency
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Template specialization hashing: Accelerates compilation of code with heavy template usage2.
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Reduced -ftime-report overhead: Now reports only monotonic runtime, making it practical for build system integration1.
3. Language-Specific Optimizations
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C++ modules: Improved support for module std (even in C++20 mode) and general module stability enhancements2.
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-fassume-sane-operators-new-delete: Enables optimizations around global operator new/delete by assuming standard-compliant behavior2.
4. Diagnostic Efficiency
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Column tracking beyond 4096: Enables precise error locations in large source files, reducing debugging time1.
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New -fdiagnostics-add-output=: Allows simultaneous output formats (e.g., SARIF + text), aiding automated analysis pipelines1.
5. Runtime Behavior
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Padding bit control: -fzero-init-padding-bits=unions ensures consistent initialization patterns, critical for cryptographic/security-sensitive code1.
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OpenMP 6.0 support: Adds unified_shared_memory and self_maps clauses for optimized offloading1.
These changes collectively target both computational efficiency and developer productivity, though specific performance gains will vary by workload and configuration.
Citations:
- https://gcc.gnu.org/gcc-15/changes.html
- https://developers.redhat.com/articles/2025/04/24/new-c-features-gcc-15
- https://www.reddit.com/r/programming/comments/1k7i0ig/gcc_the_gnu_compiler_collection_151_released/
- https://news.ycombinator.com/item?id=43792248
- https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/7/html/developer_guide/gcc-compiling-code
- https://www.techpowerup.com/forums/threads/chat-topic-gcc-15-1-released.335975/
- https://linaro.atlassian.net/browse/GNU-1418
- https://stackoverflow.com/questions/77244801/gcc-13-1-0-macos-sonoma-not-compiling-ada-or-any-languages-on-intel-or-m1-macs
I have already tested the final version of MinGW 15.1 with Harbour MiniGUI Ex. Everything is fine.
You can see a main demo example in the picture below.
What is your opinion on this matter?
Your feedback is welcome.
Best regards,
Grigory
Marcos Jarrin
José Quintas
