[Bug tree-optimization/92860] [8/9/10/11 regression] Global flags affected by -O settings are clobbered by optimize attribute

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92860

--- Comment #34 from Martin Liška <marxin at gcc dot gnu.org> ---
I don't have to do anything special in order to get pre-processed source file:

$ gcc pr88876.c -freport-bug 
pr88876.c:10:1: internal compiler error: ‘global_options’ are modified in local
context
   10 | int c() {return 0;}
      | ^~~
0xce038b cl_optimization_compare(gcc_options*, gcc_options*)
        /dev/shm/objdir/gcc/options-save.c:9822
0x8c4f88 handle_optimize_attribute
        /home/marxin/Programming/gcc/gcc/c-family/c-attribs.c:4475
0x7d4ee7 decl_attributes(tree_node**, tree_node*, int, tree_node*)
        /home/marxin/Programming/gcc/gcc/attribs.c:714
0x7f1625 start_function(c_declspecs*, c_declarator*, tree_node*)
        /home/marxin/Programming/gcc/gcc/c/c-decl.c:9177
0x84bdb7 c_parser_declaration_or_fndef
        /home/marxin/Programming/gcc/gcc/c/c-parser.c:2434
0x855453 c_parser_external_declaration
        /home/marxin/Programming/gcc/gcc/c/c-parser.c:1773
0x855f51 c_parser_translation_unit
        /home/marxin/Programming/gcc/gcc/c/c-parser.c:1646
0x855f51 c_parse_file()
        /home/marxin/Programming/gcc/gcc/c/c-parser.c:21822
0x8ae88b c_common_parse_file()
        /home/marxin/Programming/gcc/gcc/c-family/c-opts.c:1190
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
Preprocessed source stored into /tmp/cc8jx9U7.out file, please attach this to
your bugreport.