[Bug tree-optimization/90883] Generated code is worse if returned struct is unnamed

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90883

--- Comment #23 from Martin Sebor <msebor at gcc dot gnu.org> ---
I get the same failure with -m32 -mtune=generic:

spawn -ignore SIGHUP /ssd/build/gcc-svn/gcc/testsuite/g++/../../xg++
-B/ssd/buil
d/gcc-svn/gcc/testsuite/g++/../../
/src/gcc/svn/gcc/testsuite/g++.dg/tree-ssa/pr
90883.C -m32 -mtune=generic -fno-diagnostics-show-caret
-fno-diagnostics-show-li
ne-numbers -fdiagnostics-color=never -nostdinc++
-I/ssd/build/gcc-svn/x86_64-pc-
linux-gnu/32/libstdc++-v3/include/x86_64-pc-linux-gnu
-I/ssd/build/gcc-svn/x86_6
4-pc-linux-gnu/32/libstdc++-v3/include -I/src/gcc/svn/libstdc++-v3/libsupc++
-I/src/gcc/svn/libstdc++-v3/include/backward
-I/src/gcc/svn/libstdc++-v3/testsuite/util -fmessage-length=0 -O2 -Os
-fdump-tree-dse-details -std=c++11 -S -o pr90883.s
PASS: g++.dg/tree-ssa/pr90883.C   (test for excess errors)
FAIL: g++.dg/tree-ssa/pr90883.C   scan-tree-dump dse1 "Deleted redundant store:
.*.a = {}"