https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103121
--- Comment #10 from Martin Sebor <msebor at gcc dot gnu.org> --- Sorry, I've been having trouble with GDB and so I'm running two GDB sessions and I have been mixing output from both of them. I see the warning for the store to *_23 in BB 13, not for BB 12. Here's a fresh session as a sanity check: $ /build/hppa-unknown-linux-gnu/gcc-master/gcc/xgcc -B /build/hppa-unknown-linux-gnu/gcc-master/gcc -O2 -S -Wall -fdump-tree-strlen-details pr103121.ii -wrapper gdb,--args GNU gdb (GDB) 11.1 ... (gdb) b tree-ssa-strlen.c:2181 Breakpoint 1 at 0x192caed: file /src/gcc/master/gcc/tree-ssa-strlen.c, line 2181. (gdb) r Starting program: /ssd/build/hppa-unknown-linux-gnu/gcc-master/gcc/cc1plus -fpreprocessed pr103121.ii -quiet -dumpbase pr103121.ii -dumpbase-ext .ii -O2 -Wall -fdump-tree-strlen-details -o pr103121.s Breakpoint 1, strlen_pass::maybe_warn_overflow (this=0x7fffffffd880, stmt=0x7ffff4de2730, call_lhs=true, len=1, si=0x0, plus_one=false, rawmem=false) at /src/gcc/master/gcc/tree-ssa-strlen.c:2181 2181 tree tlen = build_int_cst (size_type_node, len); (gdb) p debug(gimple_bb(stmt)) <bb 12> [local count: 12992276]: *grp_name_37 = 0; goto <bb 14>; [100.00%] $1 = void (gdb) c Continuing. Breakpoint 1, strlen_pass::maybe_warn_overflow (this=0x7fffffffd880, stmt=0x7ffff4c2ea00, call_lhs=true, len=1, si=0x0, plus_one=false, rawmem=false) at /src/gcc/master/gcc/tree-ssa-strlen.c:2181 2181 tree tlen = build_int_cst (size_type_node, len); (gdb) p debug(gimple_bb(stmt)) <bb 10> [local count: 630715945]: MEM[(char *)grp_name_37 + idx_58 * 1] = 53; $2 = void (gdb) c Continuing. Breakpoint 1, strlen_pass::maybe_warn_overflow (this=0x7fffffffd880, stmt=0x7ffff4c2eb40, call_lhs=true, len=1, si=0x0, plus_one=false, rawmem=false) at /src/gcc/master/gcc/tree-ssa-strlen.c:2181 2181 tree tlen = build_int_cst (size_type_node, len); (gdb) p debug(gimple_bb(stmt)) <bb 13> [local count: 105119324]: _23 = grp_name_37 + idx_47; *_23 = 0; if (diff_seen_24 != 0) goto <bb 15>; [100.00%] else goto <bb 14>; [0.00%] $3 = void (gdb) c Continuing. ../../gcc/gcc/cp/optimize.c: In function 'tree_node* cdtor_comdat_group(tree, tree)': ../../gcc/gcc/cp/optimize.c:208:17: warning: writing 1 byte into a region of size 0 [-Wstringop-overflow=] ../../gcc/gcc/cp/optimize.c:191:40: note: at offset 1 into destination object of size 1 allocated by '__builtin_alloca' [Inferior 1 (process 11409) exited normally]
