This is a GNU extension to C99: void foo(int n) { struct S { int x[n]; }; }
It is not mentioned in the C Extensions section of the manual. -- Summary: GNU VLA-in-structure extension is undocumented Product: gcc Version: 4.4.0 Status: UNCONFIRMED Severity: minor Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: drow at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37428