[r17-1528 Regression] FAIL: g++.dg/tree-ssa/mult-negate-zeroone-1.C -std=gnu++98 scan-tree-dump-not optimized " * " on Linux/x86_64

Haochen Jiang via Gcc-regression <[email protected]> Mon, 15 Jun 2026 18:17:21 +0800
Newsgroups gmane.comp.gcc.regression,gmane.comp.gcc.patches
Message-ID <[email protected]>
On Linux/x86_64,

6bbe931ea0e8f412c81fed8a3df4a07df97821f4 is the first bad commit
commit 6bbe931ea0e8f412c81fed8a3df4a07df97821f4
Author: Kyrylo Tkachov <[email protected]>
Date:   Fri Jun 12 00:00:00 2026 +0000

    match.pd: fold (0/1) * -(0/1) into -((0/1) & (0/1))

caused

FAIL: g++.dg/tree-ssa/mult-negate-zeroone-1.C  -std=gnu++20  scan-tree-dump-not optimized " * "
FAIL: g++.dg/tree-ssa/mult-negate-zeroone-1.C  -std=gnu++26  scan-tree-dump-not optimized " * "
FAIL: g++.dg/tree-ssa/mult-negate-zeroone-1.C  -std=gnu++98  scan-tree-dump-not optimized " * "

with GCC configured with

../../gcc/configure --prefix=/export/users3/haochenj/src/gcc-bisect/master/master/r17-1528/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/tree-ssa/mult-negate-zeroone-1.C --target_board='unix{-m32}'"
$ cd {build_dir}/gcc && make check RUNTESTFLAGS="dg.exp=g++.dg/tree-ssa/mult-negate-zeroone-1.C --target_board='unix{-m32\ -march=cascadelake}'"
$ cd {build_dir}/gcc && make check RUNTESTFLAGS="dg.exp=g++.dg/tree-ssa/mult-negate-zeroone-1.C --target_board='unix{-m64}'"
$ cd {build_dir}/gcc && make check RUNTESTFLAGS="dg.exp=g++.dg/tree-ssa/mult-negate-zeroone-1.C --target_board='unix{-m64\ -march=cascadelake}'"

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