On Tue, May 19, 2026 at 10:09 PM Haochen Jiang <[email protected]> wrote: > > On Linux/x86_64, > > acfdad706d8acca6c4ed6ef3b63c2e02f1c47881 is the first bad commit > commit acfdad706d8acca6c4ed6ef3b63c2e02f1c47881 > Author: Nathan Myers <[email protected]> > Date: Fri Apr 3 23:55:39 2026 -0400 > > libstdc++: Use allocate_at_least in vector, string (P0401) [PR118030] > > caused > > FAIL: g++.dg/opt/shrink-wrapping-vector-1.C -std=gnu++98 scan-rtl-dump > pro_and_epilogue "Performing shrink-wrapping"
I filed https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125400 for the missed optimization which is causing the missed shrink wrapping. If I can figure out how to xfail it for C++98 only I will unless someone beats me to it. Note It fails on all the specified targets in the testcase as it is generic issue. Thanks, Andrea > > with GCC configured with > > ../../gcc/configure > --prefix=/export/users3/haochenj/src/gcc-bisect/master/master/r17-603/usr > --enable-clocale=gnu --with-system-zlib --with-demangler-in-ld > --with-fpmath=sse --enable-languages=c,c++,fortran --enable-cet --without-isl > --enable-libmpx x86_64-linux --disable-bootstrap > > To reproduce: > > $ cd {build_dir}/gcc && make check > RUNTESTFLAGS="dg.exp=g++.dg/opt/shrink-wrapping-vector-1.C > --target_board='unix{-m64}'" > $ cd {build_dir}/gcc && make check > RUNTESTFLAGS="dg.exp=g++.dg/opt/shrink-wrapping-vector-1.C > --target_board='unix{-m64\ -march=cascadelake}'" > > (Please directly reply to this email for question about this report.) > (If you met problems with cascadelake related, disabling AVX512F in command > line might save that.) > (However, please make sure that there is no potential problems with AVX512.)
