https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88584
Bug ID: 88584 Summary: GCC thinks that the type is complete dispite shaddowing. Product: gcc Version: 9.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c Assignee: unassigned at gcc dot gnu.org Reporter: anders.granlund.0 at gmail dot com Target Milestone: --- Test program (prog.c): int a[1] = { 0 }; int main() { int a; { extern int a[]; sizeof (a); } } Compilation command line: gcc prog.c -Wall -Wextra -std=c11 -pedantic-errors Observed behaviour: No error messages are outputed. Expected behaviour: An error message. Because the file scope declaration is shaddowed a should not have a complete type in sizeof (a). Note: Clang outputs the expected error message for the program.