(MSYS2/MinGW, GCC 9.2.0) Slice.cpp: reading 256 bytes from a region of size 64

[ligh_de]

Trying to build git HEAD in MSYS2/MinGW with GCC 9.2.0:

CFLAGS: -mthreads -mtune=generic -O2 -pipe
LDFLAGS: -pipe -static-libgcc -static-libstdc++
ninja 
...
[72/191] Building CXX object source/Lib/CommonLib/CMakeFiles/CommonLib.dir/Slice.cpp.o
FAILED: source/Lib/CommonLib/CMakeFiles/CommonLib.dir/Slice.cpp.o 
E:\MABS\local32\bin\g++.bat  -DENABLE_SPLIT_PARALLELISM=0 -I../source/Lib/CommonLib/. -I../source/Lib/CommonLib/.. -I../source/Lib/CommonLib/./x86 -I../source/Lib/CommonLib/../libmd5 -mthreads -mtune=generic -O2 -pipe -fopenmp -O3 -DNDEBUG   -Wall -fdiagnostics-show-option -Werror -Wno-sign-compare -Wno-class-memaccess -msse4.1 -mthreads -std=gnu++11 -MD -MT source/Lib/CommonLib/CMakeFiles/CommonLib.dir/Slice.cpp.o -MF source\Lib\CommonLib\CMakeFiles\CommonLib.dir\Slice.cpp.o.d -o source/Lib/CommonLib/CMakeFiles/CommonLib.dir/Slice.cpp.o -c ../source/Lib/CommonLib/Slice.cpp
../source/Lib/CommonLib/Slice.cpp: In member function 'bool ScalingList::isNotDefaultScalingList()':
../source/Lib/CommonLib/Slice.cpp:2015:23: error: 'int __builtin_memcmp_eq(const void*, const void*, unsigned int)' reading 256 bytes from a region of size 64 [-Werror=stringop-overflow=]
 2015 |       if( !( !::memcmp(getScalingListAddress(sizeId, listId), getScalingListDefaultAddress(sizeId, listId), sizeof(int)*std::min(MAX_MATRIX_COEF_NUM, (int)g_scalingListSize[sizeId])) // check value of matrix
      |               ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../source/Lib/CommonLib/Slice.cpp:2015:23: error: 'int __builtin_memcmp_eq(const void*, const void*, unsigned int)' reading 256 bytes from a region of size 64 [-Werror=stringop-overflow=]
../source/Lib/CommonLib/Slice.cpp:2015:23: error: 'int __builtin_memcmp_eq(const void*, const void*, unsigned int)' reading 256 bytes from a region of size 64 [-Werror=stringop-overflow=]
../source/Lib/CommonLib/Slice.cpp:2015:23: error: 'int __builtin_memcmp_eq(const void*, const void*, unsigned int)' reading 256 bytes from a region of size 64 [-Werror=stringop-overflow=]
../source/Lib/CommonLib/Slice.cpp:2015:23: error: 'int __builtin_memcmp_eq(const void*, const void*, unsigned int)' reading 256 bytes from a region of size 64 [-Werror=stringop-overflow=]
../source/Lib/CommonLib/Slice.cpp:2015:23: error: 'int __builtin_memcmp_eq(const void*, const void*, unsigned int)' reading 256 bytes from a region of size 64 [-Werror=stringop-overflow=]
../source/Lib/CommonLib/Slice.cpp:2015:23: error: 'int __builtin_memcmp_eq(const void*, const void*, unsigned int)' reading 256 bytes from a region of size 64 [-Werror=stringop-overflow=]
../source/Lib/CommonLib/Slice.cpp:2015:23: error: 'int __builtin_memcmp_eq(const void*, const void*, unsigned int)' reading 256 bytes from a region of size 64 [-Werror=stringop-overflow=]
cc1plus.exe: all warnings being treated as errors

[abe.kiyo]

I think this issue is related to the discussion of Merge Requests !962.
​https://vcgit.hhi.fraunhofer.de/jvet/VVCSoftware_VTM/merge_requests/962

[ligh_de]

Yes, most probably related; I see Jamaika is already involved.

[abe.kiyo]

I have created new merge request to solve this issue.
​https://vcgit.hhi.fraunhofer.de/jvet/VVCSoftware_VTM/merge_requests/974

[Jamaika]

Thanks abe.kiyo.
Ligh_de can also report the problem to MSYS2/MinGW, because I haven't done.

[ligh_de]

Why would the package maintainers of MSYS2 be interested? They do not develop GCC. They only provide it as POSIX/Linux like cross-compilation environment.

But it was mentioned in the ​media-autobuild suite, a script for automated building of several codecs, up to an ffmpeg using most of them, running in a permanently updated MSYS2/MinGW subsystem under Windows. Here I will report when you merged the patch to fix the compilation.