$ i586-pc-msdosdjgpp-g++ -o a a.cc -Ofast -std=c++20 -s -flto
In file included from
d:\msys64\i586-pc-msdosdjgpp\lib\gcc\i586-pc-msdosdjgpp\11.0.1\include\immintrin.h:43,
from ../include/fast_io_core_impl/intrinsics.h:5,
from ../include/fast_io_core.h:28,
The assembly GCC generates are just wrong, very wrong here. People have
reported the similar bugs since 2015 over and over again but GCC still could
not get it done right. Even MSVC is doing the right thing.
If you are not going to fix them, okay, I will start to write assembly manually.
I have
https://github.com/euloanty/fast_io/blob/master/examples/0036.concepts_check/iostrm.cc
cqwrteur@DESKTOP-7H7UHQ9:/mnt/d/hg/fast_io/examples/build$ ninja
[1/2] Building CXX object CMakeFiles/iostrm.dir/0036.concepts_check/iostrm.cc.o
FAILED: CMakeFiles/iostrm.dir/0036.concepts_check/iostrm.cc.o
/u
