https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83656
--- Comment #6 from Martin Sebor <msebor at gcc dot gnu.org> --- Author: msebor Date: Thu Nov 15 22:18:54 2018 New Revision: 266194 URL: https://gcc.gnu.org/viewcvs?rev=266194&root=gcc&view=rev Log: PR c/83656 - missing -Wbuiltin-declaration-mismatch on declaration without prototype gcc/c/ChangeLog: PR c/83656 * c-decl.c (header_for_builtin_fn): Declare. (diagnose_mismatched_decls): Diagnose declarations of built-in functions without a prototype. * c-typeck.c (maybe_warn_builtin_no_proto_arg): New function. (convert_argument): Same. (convert_arguments): Factor code out into convert_argument. Detect mismatches between built-in formal arguments in calls to built-in without prototype. (build_conditional_expr): Same. (type_or_builtin_type): New function. (convert_for_assignment): Add argument. Conditionally issue warnings instead of errors for mismatches. gcc/testsuite/ChangeLog: PR c/83656 * gcc.dg/20021006-1.c * gcc.dg/Wbuiltin-declaration-mismatch.c: New test. * gcc.dg/Wbuiltin-declaration-mismatch-2.c: New test. * gcc.dg/Wbuiltin-declaration-mismatch-3.c: New test. * gcc.dg/Wbuiltin-declaration-mismatch-4.c: New test. * gcc.dg/Walloca-16.c: Adjust. * gcc.dg/Wrestrict-4.c: Adjust. * gcc.dg/Wrestrict-5.c: Adjust. * gcc.dg/atomic/stdatomic-generic.c: Adjust. * gcc.dg/atomic/stdatomic-lockfree.c: Adjust. * gcc.dg/initpri1.c: Adjust. * gcc.dg/pr15698-1.c: Adjust. * gcc.dg/pr69156.c: Adjust. * gcc.dg/pr83463.c: Adjust. * gcc.dg/redecl-4.c: Adjust. * gcc.dg/tls/thr-init-2.c: Adjust. * gcc.dg/torture/pr55890-2.c: Adjust. * gcc.dg/torture/pr55890-3.c: Adjust. * gcc.dg/torture/pr67741.c: Adjust. * gcc.dg/torture/stackalign/sibcall-1.c: Adjust. * gcc.dg/torture/tls/thr-init-1.c: Adjust. * gcc.dg/tree-ssa/builtins-folding-gimple-ub.c: Adjust. Added: trunk/gcc/testsuite/gcc.dg/Wbuiltin-declaration-mismatch-2.c trunk/gcc/testsuite/gcc.dg/Wbuiltin-declaration-mismatch-3.c trunk/gcc/testsuite/gcc.dg/Wbuiltin-declaration-mismatch-4.c trunk/gcc/testsuite/gcc.dg/Wbuiltin-declaration-mismatch.c Modified: trunk/gcc/c/ChangeLog trunk/gcc/c/c-decl.c trunk/gcc/c/c-typeck.c trunk/gcc/doc/invoke.texi trunk/gcc/testsuite/ChangeLog trunk/gcc/testsuite/gcc.dg/20021006-1.c trunk/gcc/testsuite/gcc.dg/Walloca-16.c trunk/gcc/testsuite/gcc.dg/Wrestrict-4.c trunk/gcc/testsuite/gcc.dg/Wrestrict-5.c trunk/gcc/testsuite/gcc.dg/atomic/stdatomic-generic.c trunk/gcc/testsuite/gcc.dg/atomic/stdatomic-lockfree.c trunk/gcc/testsuite/gcc.dg/initpri1.c trunk/gcc/testsuite/gcc.dg/pr15698-1.c trunk/gcc/testsuite/gcc.dg/pr69156.c trunk/gcc/testsuite/gcc.dg/pr83463.c trunk/gcc/testsuite/gcc.dg/redecl-4.c trunk/gcc/testsuite/gcc.dg/tls/thr-init-2.c trunk/gcc/testsuite/gcc.dg/torture/pr55890-2.c trunk/gcc/testsuite/gcc.dg/torture/pr55890-3.c trunk/gcc/testsuite/gcc.dg/torture/pr67741.c trunk/gcc/testsuite/gcc.dg/torture/pr71816.c trunk/gcc/testsuite/gcc.dg/torture/stackalign/sibcall-1.c trunk/gcc/testsuite/gcc.dg/torture/tls/thr-init-1.c trunk/gcc/testsuite/gcc.dg/tree-ssa/builtins-folding-gimple-ub.c