[PATCH 3/3] Revert "hardening: Disable GCC randstruct for COMPILE_TEST"

[Thiago Jung Bauermann]

Hello,

This commit was reported by our CI as breaking the allmodconfig build for
the arm and arm64 architectures when using GCC 15. This is due to
https://github.com/KSPP/linux/issues/367 :

-00:05:08 *** WARNING *** there are active plugins, do not report this as a bug unless you can reproduce it without enabling any plugins.
00:05:08 Event                            | Plugins
00:05:08 PLUGIN_FINISH_TYPE               | randomize_layout_plugin
00:05:08 PLUGIN_FINISH_DECL               | randomize_layout_plugin
00:05:08 PLUGIN_ATTRIBUTES                | latent_entropy_plugin randomize_layout_plugin
00:05:08 PLUGIN_START_UNIT                | latent_entropy_plugin stackleak_plugin
00:05:08 PLUGIN_ALL_IPA_PASSES_START      | randomize_layout_plugin
00:05:08 arch/arm64/kernel/kexec_image.c:132:14: internal compiler error: in comptypes_check_enum_int, at c/c-typeck.cc:1519
00:05:08   132 | const struct kexec_file_ops kexec_image_ops = {
00:05:08       |              ^~~~~~~~~~~~~~
00:05:08 0x225bdff internal_error(char const*, ...)
00:05:08 	../../../../../../gcc/gcc/diagnostic-global-context.cc:517
00:05:08 0x7cb197 fancy_abort(char const*, int, char const*)
00:05:08 	../../../../../../gcc/gcc/diagnostic.cc:1803
00:05:08 0x81f0e7 comptypes_check_enum_int(tree_node*, tree_node*, bool*)
00:05:08 	../../../../../../gcc/gcc/c/c-typeck.cc:1519
00:05:08 0x81f0e7 comptypes_check_enum_int(tree_node*, tree_node*, bool*)
00:05:08 	../../../../../../gcc/gcc/c/c-typeck.cc:1513
00:05:08 0x7e3b83 diagnose_mismatched_decls
00:05:08 	../../../../../../gcc/gcc/c/c-decl.cc:2170
00:05:08 0x7e64f3 duplicate_decls
00:05:08 	../../../../../../gcc/gcc/c/c-decl.cc:3169
00:05:08 0x7ea1eb pushdecl(tree_node*)
00:05:08 	../../../../../../gcc/gcc/c/c-decl.cc:3376
00:05:08 0x803c03 start_decl(c_declarator*, c_declspecs*, bool, tree_node*, bool, unsigned long*)
00:05:08 	../../../../../../gcc/gcc/c/c-decl.cc:5755
00:05:08 0x864c67 c_parser_declaration_or_fndef
00:05:08 	../../../../../../gcc/gcc/c/c-parser.cc:2851
00:05:08 0x8a7b33 c_parser_external_declaration
00:05:08 	../../../../../../gcc/gcc/c/c-parser.cc:2110
00:05:08 0x8a8ba3 c_parser_translation_unit
00:05:08 	../../../../../../gcc/gcc/c/c-parser.cc:1964
00:05:08 0x8a8ba3 c_parse_file()
00:05:08 	../../../../../../gcc/gcc/c/c-parser.cc:29839
00:05:08 0x931eff c_common_parse_file()
00:05:08 	../../../../../../gcc/gcc/c-family/c-opts.cc:1385
00:05:08 Please submit a full bug report, with preprocessed source (by using -freport-bug).
00:05:08 Please include the complete backtrace with any bug report.
00:05:08 See <https://gcc.gnu.org/bugs/> for instructions.
00:05:08 make[4]: *** [scripts/Makefile.build:203: arch/arm64/kernel/kexec_image.o] Error 1

The same error repeats for several other source files.