https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88526
Bug ID: 88526 Summary: gcc accepts ill-formed program with sizeof (int [*]) 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: --- Consider the following C11 program (prog.c): void f(int a[sizeof(int [*])]); int main() { } Compiling it with gcc prog.c -std=c11 -pedantic-errors gives no errors. The expected behaviour is that it should compile with at least one error. This becuase the flag -pedantic-errors was used and because the program is incorrect according to the C11 standard (taking sizeof int [*] should not be possible since it is not a complete type).