https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119722
Bug ID: 119722
Summary: wrong code with _BitInt(),
__builtin_stdc_rotate_left() at -O2 -fno-tree-forwprop
-fno-tree-copy-prop -fno-tree-fre
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Keywords: wrong-code
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: zsojka at seznam dot cz
CC: jakub at gcc dot gnu.org
Target Milestone: ---
Host: x86_64-pc-linux-gnu
Target: x86_64-pc-linux-gnu
Created attachment 61070
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=61070&action=edit
reduced testcase
Output:
$ x86_64-pc-linux-gnu-gcc -O2 -fno-tree-forwprop -fno-tree-copy-prop
-fno-tree-fre -Wall -W testcase.c
testcase.c: In function 'foo':
testcase.c:7:75: warning: unused variable 'unused' [-Wunused-variable]
7 | unsigned s = (unsigned _BitInt(50))(g >> 50) + ({ unsigned
_BitInt(300) unused; b; });
|
^~~~~~
$ ./a.out
Aborted
$ x86_64-pc-linux-gnu-gcc -v
Using built-in specs.
COLLECT_GCC=/repo/gcc-trunk/binary-latest-amd64/bin/x86_64-pc-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-20250410183952-r15-9366-g1f32b87117b0e2-checking-release-nobootstrap-amd64/bin/../libexec/gcc/x86_64-pc-linux-gnu/15.0.1/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /repo/gcc-trunk//configure --enable-languages=c,c++
--enable-valgrind-annotations --disable-nls --enable-checking=release
--disable-bootstrap --with-cloog --with-ppl --with-isl
--build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu
--target=x86_64-pc-linux-gnu --with-ld=/usr/bin/x86_64-pc-linux-gnu-ld
--with-as=/usr/bin/x86_64-pc-linux-gnu-as --enable-libsanitizer
--disable-libstdcxx-pch
--prefix=/repo/gcc-trunk//binary-trunk-20250410183952-r15-9366-g1f32b87117b0e2-checking-release-nobootstrap-amd64
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 15.0.1 20250410 (experimental) (GCC)
