https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83367
Bug ID: 83367 Summary: static global constructors stack memory clobbering Product: gcc Version: 7.2.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: rtl-optimization Assignee: unassigned at gcc dot gnu.org Reporter: weilercdale at gmail dot com Target Milestone: --- Created attachment 42835 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=42835&action=edit I've combined three files here because Bugzilla does not support adding multiple attachment files? I spent several hours trying to reduce this to the most minimal test case I could but the compiler is very picky about the static global constructors being in their own translation unit to trigger the problems. Test.cpp contains the core code for a "test" framework that accepts registering tests and subtests through maintaining a static linked list as static global constructors are invoked. Test.h contains the definitions needed to define tests in a seperate translation unit Tests.cpp (again because putting it inline the Test.cpp file does not exibit the problem.) Test.cpp contains a test + subtest that triggers the bug, however the conditionally excluded equivlant example (avoiding cTestRegister) does not exibit the problem either. When you compile with -fsanitize=address asan reports stack memory corruption, as does valgrind if you run it a couple times. It should print "b\n\a\n", as it does with clang/msvc (at all optimization levels) and gcc at -O0, any optimization level will lead to clobbering, garbage output and in most cases Illegal instruction exceptions.