commit: 06aaa0e02fa008fe15d2b1873627e067a3c9db7d
[log]
author: Martin Storsjö <martin@martin.st>
Tue Sep 16 14:23:36 2025 +0300
committer: Martin Storsjö <martin@martin.st>
Tue Sep 16 23:13:37 2025 +0300
tree: ce21b9fa515a72d6108c8113d4bca5b7afbd4d53
parent: 0df46c4f5a130d1c9046494bfab903a6c415a810 [diff]

[CMake] Disable more noisy GCC warnings (#159044)

This disables the following very noisy warning:

    In file included from /usr/include/c++/13/string:51,
                     from /usr/include/c++/13/bits/locale_classes.h:40,
                     from /usr/include/c++/13/bits/ios_base.h:41,
                     from /usr/include/c++/13/streambuf:43,
                     from /usr/include/c++/13/bits/streambuf_iterator.h:35,
                     from /usr/include/c++/13/iterator:66,
                     from ../include/llvm/ADT/ADL.h:13,
                     from ../include/llvm/ADT/DenseMap.h:17,
                     from ../lib/Transforms/Vectorize/VPlanAnalysis.h:12,
                     from ../lib/Transforms/Vectorize/VPlan.h:27,
                     from ../lib/Transforms/Vectorize/LoopVectorizationPlanner.h:27,                 from ../lib/Transforms/Vectorize/VPlanConstruction.cpp:14:
    In static member function ‘static _Up* std::__copy_move<_IsMove, true, std::random_access_iterator_tag>::__copy_m(_Tp*, _Tp*, _Up*) [with _Tp = llvm::VPBlockBase*; _Up = llvm::VPBlockBase*; bool _IsMove = true]’,
        inlined from ‘_OI std::__copy_move_a2(_II, _II, _OI) [with bool _IsMove = true; _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:506:30,
        inlined from ‘_OI std::__copy_move_a1(_II, _II, _OI) [with bool _IsMove = true; _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:533:42,
        inlined from ‘_OI std::__copy_move_a(_II, _II, _OI) [with bool _IsMove = true; _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:540:31,
        inlined from ‘_OI std::move(_II, _II, _OI) [with _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:665:38,
        inlined from ‘llvm::SmallVectorImpl<T>& llvm::SmallVectorImpl<T>::operator=(llvm::SmallVectorImpl<T>&&) [with T = llvm::VPBlockBase*]’ at ../include/llvm/ADT/SmallVector.h:1071:25,
        inlined from ‘llvm::SmallVector<T, N>& llvm::SmallVector<T, N>::operator=(llvm::SmallVector<T, N>&&) [with T = llvm::VPBlockBase*; unsigned int N = 1]’ at ../include/llvm/ADT/SmallVector.h:1259:36,
        inlined from ‘static void llvm::DomTreeBuilder::SemiNCAInfo<DomTreeT>::CalculateFromScratch(DomTreeT&, BatchUpdatePtr) [with DomTreeT = llvm::DominatorTreeBase<llvm::VPBlockBase, false>]’ at ../include/llvm/Support/GenericDomTreeConstruction.h:578:14:
    /usr/include/c++/13/bits/stl_algobase.h:437:30: warning: ‘void* __builtin_memmove(void*, const void*, long unsigned int)’ forming offset 24 is out of the bounds [0, 24] of object ‘<anonymous>’ with type ‘llvm::DomTreeBuilder::SemiNCAInfo<llvm::DominatorTreeBase<llvm::VPBlockBase, false> >::RootsT’ {aka ‘llvm::SmallVector<llvm::VPBlockBase*, 1>’} [-Warray-bounds=]
      437 |             __builtin_memmove(__result, __first, sizeof(_Tp) * _Num);
          |             ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    In file included from ../lib/Transforms/Vectorize/VPlanDominatorTree.h:23,
                     from ../lib/Transforms/Vectorize/VPlanConstruction.cpp:17:
    ../include/llvm/Support/GenericDomTreeConstruction.h: In static member function ‘static void llvm::DomTreeBuilder::SemiNCAInfo<DomTreeT>::CalculateFromScratch(DomTreeT&, BatchUpdatePtr) [with DomTreeT = llvm::DominatorTreeBase<llvm::VPBlockBase, false>]’:
    ../include/llvm/Support/GenericDomTreeConstruction.h:578:25: note: ‘<anonymous>’ declared here
      578 |     DT.Roots = FindRoots(DT, PostViewBUI);
          |                ~~~~~~~~~^~~~~~~~~~~~~~~~~
    In static member function ‘static _Up* std::__copy_move<_IsMove, true, std::random_access_iterator_tag>::__copy_m(_Tp*, _Tp*, _Up*) [with _Tp = llvm::VPBlockBase*; _Up = llvm::VPBlockBase*; bool _IsMove = true]’,
        inlined from ‘_OI std::__copy_move_a2(_II, _II, _OI) [with bool _IsMove = true; _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:506:30,
        inlined from ‘_OI std::__copy_move_a1(_II, _II, _OI) [with bool _IsMove = true; _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:533:42,
        inlined from ‘_OI std::__copy_move_a(_II, _II, _OI) [with bool _IsMove = true; _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:540:31,
        inlined from ‘_OI std::move(_II, _II, _OI) [with _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:665:38,
        inlined from ‘llvm::SmallVectorImpl<T>& llvm::SmallVectorImpl<T>::operator=(llvm::SmallVectorImpl<T>&&) [with T = llvm::VPBlockBase*]’ at ../include/llvm/ADT/SmallVector.h:1094:14,
        inlined from ‘llvm::SmallVector<T, N>& llvm::SmallVector<T, N>::operator=(llvm::SmallVector<T, N>&&) [with T = llvm::VPBlockBase*; unsigned int N = 1]’ at ../include/llvm/ADT/SmallVector.h:1259:36,
        inlined from ‘static void llvm::DomTreeBuilder::SemiNCAInfo<DomTreeT>::CalculateFromScratch(DomTreeT&, BatchUpdatePtr) [with DomTreeT = llvm::DominatorTreeBase<llvm::VPBlockBase, false>]’ at ../include/llvm/Support/GenericDomTreeConstruction.h:578:14:
    /usr/include/c++/13/bits/stl_algobase.h:437:30: warning: ‘void* __builtin_memmove(void*, const void*, long unsigned int)’ forming offset 24 is out of the bounds [0, 24] of object ‘<anonymous>’ with type ‘llvm::DomTreeBuilder::SemiNCAInfo<llvm::DominatorTreeBase<llvm::VPBlockBase, false> >::RootsT’ {aka ‘llvm::SmallVector<llvm::VPBlockBase*, 1>’} [-Warray-bounds=]
      437 |             __builtin_memmove(__result, __first, sizeof(_Tp) * _Num);
          |             ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ../include/llvm/Support/GenericDomTreeConstruction.h: In static member function ‘static void llvm::DomTreeBuilder::SemiNCAInfo<DomTreeT>::CalculateFromScratch(DomTreeT&, BatchUpdatePtr) [with DomTreeT = llvm::DominatorTreeBase<llvm::VPBlockBase, false>]’:
    ../include/llvm/Support/GenericDomTreeConstruction.h:578:25: note: ‘<anonymous>’ declared here
      578 |     DT.Roots = FindRoots(DT, PostViewBUI);
          |                ~~~~~~~~~^~~~~~~~~~~~~~~~~

In a regular build, there's currently 14 such warning instances,
but since they are so large and noisy, they are very disruptive,
and they don't seem to be an actual issue in the LLVM code base.

With the -Warray-bounds warning disabled, the build instead ends
up with 9 similar warnings of the kind -Wstringop-overread:

    In file included from /usr/include/c++/13/string:51,
                     from /usr/include/c++/13/bits/locale_classes.h:40,
                     from /usr/include/c++/13/bits/ios_base.h:41,
                     from /usr/include/c++/13/streambuf:43,
                     from /usr/include/c++/13/bits/streambuf_iterator.h:35,
                     from /usr/include/c++/13/iterator:66,
                     from ../include/llvm/ADT/ADL.h:13,
                     from ../include/llvm/ADT/DenseMap.h:17,
                     from ../lib/Transforms/Vectorize/VPlanAnalysis.h:12,
                     from ../lib/Transforms/Vectorize/VPlan.h:27,
                     from ../lib/Transforms/Vectorize/LoopVectorizationPlanner.h:27,                 from ../lib/Transforms/Vectorize/VPlanConstruction.cpp:14:
    In static member function ‘static _Up* std::__copy_move<_IsMove, true, std::random_access_iterator_tag>::__copy_m(_Tp*, _Tp*, _Up*) [with _Tp = llvm::VPBlockBase*; _Up = llvm::VPBlockBase*; bool _IsMove = true]’,
        inlined from ‘_OI std::__copy_move_a2(_II, _II, _OI) [with bool _IsMove = true; _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:506:30,
        inlined from ‘_OI std::__copy_move_a1(_II, _II, _OI) [with bool _IsMove = true; _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:533:42,
        inlined from ‘_OI std::__copy_move_a(_II, _II, _OI) [with bool _IsMove = true; _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:540:31,
        inlined from ‘_OI std::move(_II, _II, _OI) [with _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:665:38,
        inlined from ‘llvm::SmallVectorImpl<T>& llvm::SmallVectorImpl<T>::operator=(llvm::SmallVectorImpl<T>&&) [with T = llvm::VPBlockBase*]’ at ../include/llvm/ADT/SmallVector.h:1071:25,
        inlined from ‘llvm::SmallVector<T, N>& llvm::SmallVector<T, N>::operator=(llvm::SmallVector<T, N>&&) [with T = llvm::VPBlockBase*; unsigned int N = 1]’ at ../include/llvm/ADT/SmallVector.h:1259:36,
        inlined from ‘static void llvm::DomTreeBuilder::SemiNCAInfo<DomTreeT>::CalculateFromScratch(DomTreeT&, BatchUpdatePtr) [with DomTreeT = llvm::DominatorTreeBase<llvm::VPBlockBase, false>]’ at ../include/llvm/Support/GenericDomTreeConstruction.h:578:14:
    /usr/include/c++/13/bits/stl_algobase.h:437:30: warning: ‘void* __builtin_memmove(void*, const void*, long unsigned int)’ reading between 9 and 34359738360 bytes from a region of size 8 [-Wstringop-overread]
      437 |             __builtin_memmove(__result, __first, sizeof(_Tp) * _Num);
          |             ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    In file included from ../lib/Transforms/Vectorize/VPlanDominatorTree.h:23,
                     from ../lib/Transforms/Vectorize/VPlanConstruction.cpp:17:
    ../include/llvm/Support/GenericDomTreeConstruction.h: In static member function ‘static void llvm::DomTreeBuilder::SemiNCAInfo<DomTreeT>::CalculateFromScratch(DomTreeT&, BatchUpdatePtr) [with DomTreeT = llvm::DominatorTreeBase<llvm::VPBlockBase, false>]’:
    ../include/llvm/Support/GenericDomTreeConstruction.h:578:25: note: at offset 16 into source object ‘<anonymous>’ of size 24
      578 |     DT.Roots = FindRoots(DT, PostViewBUI);
          |                ~~~~~~~~~^~~~~~~~~~~~~~~~~
    In static member function ‘static _Up* std::__copy_move<_IsMove, true, std::random_access_iterator_tag>::__copy_m(_Tp*, _Tp*, _Up*) [with _Tp = llvm::VPBlockBase*; _Up = llvm::VPBlockBase*; bool _IsMove = true]’,
        inlined from ‘_OI std::__copy_move_a2(_II, _II, _OI) [with bool _IsMove = true; _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:506:30,
        inlined from ‘_OI std::__copy_move_a1(_II, _II, _OI) [with bool _IsMove = true; _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:533:42,
        inlined from ‘_OI std::__copy_move_a(_II, _II, _OI) [with bool _IsMove = true; _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:540:31,
        inlined from ‘_OI std::move(_II, _II, _OI) [with _II = llvm::VPBlockBase**; _OI = llvm::VPBlockBase**]’ at /usr/include/c++/13/bits/stl_algobase.h:665:38,
        inlined from ‘llvm::SmallVectorImpl<T>& llvm::SmallVectorImpl<T>::operator=(llvm::SmallVectorImpl<T>&&) [with T = llvm::VPBlockBase*]’ at ../include/llvm/ADT/SmallVector.h:1094:14,
        inlined from ‘llvm::SmallVector<T, N>& llvm::SmallVector<T, N>::operator=(llvm::SmallVector<T, N>&&) [with T = llvm::VPBlockBase*; unsigned int N = 1]’ at ../include/llvm/ADT/SmallVector.h:1259:36,
        inlined from ‘static void llvm::DomTreeBuilder::SemiNCAInfo<DomTreeT>::CalculateFromScratch(DomTreeT&, BatchUpdatePtr) [with DomTreeT = llvm::DominatorTreeBase<llvm::VPBlockBase, false>]’ at ../include/llvm/Support/GenericDomTreeConstruction.h:578:14:
    /usr/include/c++/13/bits/stl_algobase.h:437:30: warning: ‘void* __builtin_memmove(void*, const void*, long unsigned int)’ reading between 9 and 34359738352 bytes from a region of size 8 [-Wstringop-overread]
      437 |             __builtin_memmove(__result, __first, sizeof(_Tp) * _Num);
          |             ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    ../include/llvm/Support/GenericDomTreeConstruction.h: In static member function ‘static void llvm::DomTreeBuilder::SemiNCAInfo<DomTreeT>::CalculateFromScratch(DomTreeT&, BatchUpdatePtr) [with DomTreeT = llvm::DominatorTreeBase<llvm::VPBlockBase, false>]’:
    ../include/llvm/Support/GenericDomTreeConstruction.h:578:25: note: at offset 16 into source object ‘<anonymous>’ of size 24
      578 |     DT.Roots = FindRoots(DT, PostViewBUI);
          |                ~~~~~~~~~^~~~~~~~~~~~~~~~~

Disable both of these, as they are extremely spammy and seem to
alert on things that aren't an issue in LLVM.

llvm/cmake/modules/HandleLLVMOptions.cmake[diff]

1 file changed

tree: ce21b9fa515a72d6108c8113d4bca5b7afbd4d53

README.md

The LLVM Compiler Infrastructure

Welcome to the LLVM project!

This repository contains the source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and run-time environments.

The LLVM project has multiple components. The core of the project is itself called “LLVM”. This contains all of the tools, libraries, and header files needed to process intermediate representations and convert them into object files. Tools include an assembler, disassembler, bitcode analyzer, and bitcode optimizer.

C-like languages use the Clang frontend. This component compiles C, C++, Objective-C, and Objective-C++ code into LLVM bitcode -- and from there into object files, using LLVM.

Other components include: the libc++ C++ standard library, the LLD linker, and more.

Getting the Source Code and Building LLVM

Consult the Getting Started with LLVM page for information on building and running LLVM.

For information on how to contribute to the LLVM project, please take a look at the Contributing to LLVM guide.

Getting in touch

Join the LLVM Discourse forums, Discord chat, LLVM Office Hours or Regular sync-ups.

The LLVM project has adopted a code of conduct for participants to all modes of communication within the project.