[Bug c/101292] New: recent valgrind error in warning-control.cc

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101292

            Bug ID: 101292
           Summary: recent valgrind error in warning-control.cc
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dcb314 at hotmail dot com
  Target Milestone: ---

Recent gcc trunk build does:

/home/dcb/gcc/working.valgrind/./gcc/xgcc -shared-libgcc
-B/home/dcb/gcc/working.valgrind/./gcc -nostdinc++
-L/home/dcb/gcc/working.valgrind/x86_64-pc-linux-gnu/libstdc++-v3/src
-L/home/dcb/gcc/working.valgrind/x86_64-pc-linux-gnu/libstdc++-v3/src/.libs
-L/home/dcb/gcc/working.valgrind/x86_64-pc-linux-gnu/libstdc++-v3/libsupc++/.libs
-B/home/dcb/gcc/results.20210701.valgrind/x86_64-pc-linux-gnu/bin/
-B/home/dcb/gcc/results.20210701.valgrind/x86_64-pc-linux-gnu/lib/ -isystem
/home/dcb/gcc/results.20210701.valgrind/x86_64-pc-linux-gnu/include -isystem
/home/dcb/gcc/results.20210701.valgrind/x86_64-pc-linux-gnu/sys-include    -x
c++-header -nostdinc++ -g -O3 -D_GNU_SOURCE 
-I/home/dcb/gcc/working.valgrind/x86_64-pc-linux-gnu/libstdc++-v3/include/x86_64-pc-linux-gnu
-I/home/dcb/gcc/working.valgrind/x86_64-pc-linux-gnu/libstdc++-v3/include
-I/home/dcb/gcc/trunk.git/libstdc++-v3/libsupc++  -O2 -g
/home/dcb/gcc/trunk.git/libstdc++-v3/include/precompiled/extc++.h -o
x86_64-pc-linux-gnu/bits/extc++.h.gch/O2g.gch
==29810== Invalid read of size 4
==29810==    at 0x114F9C0: put (hash-map.h:179)
==29810==    by 0x114F9C0: copy_warning<tree_node*, const tree_node*>
(warning-control.cc:194)
==29810==    by 0x114F9C0: copy_warning(tree_node*, tree_node const*)
(warning-control.cc:213)
==29810==    by 0x6C0F5F: cp_fold(tree_node*) (cp-gimplify.c:2718)

This is for git hash 91c771ec8a3b6497. This error did not occur
last time I tried this build with git hash b4e21c80462682c4.