the folowing testcase does a casting which results in undefined behaviour but gcc does not warn about it.
ypedef int (*bar_t)(int x, int y, ...); int foo(int x, int y) { return x+y; } void f(int x, int y) { bar_t bar; /* Cast foo to variadic type... undefined behaviour */ bar = (bar_t) foo; (*bar)(x,y); } -- Summary: gcc does not warn about casting non-variadic types to variadic types Product: gcc Version: 4.4.3 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: raj dot khem at gmail dot com GCC build triplet: x86_64-linux-gnu GCC host triplet: x86_64-linux-gnu GCC target triplet: x86_64-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44586