From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2122) id 578913850849; Mon, 13 Jun 2022 21:55:12 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 578913850849 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Jason Merrill To: gcc-cvs@gcc.gnu.org Subject: [gcc r13-1076] ubsan: -Wreturn-type and ubsan trap-on-error X-Act-Checkin: gcc X-Git-Author: Jason Merrill X-Git-Refname: refs/heads/master X-Git-Oldrev: 72b185189f914a412ae39776cd284dfaeaf2213b X-Git-Newrev: 2c11662391bafd74c9d19bf7626b7bcef41c1323 Message-Id: <20220613215512.578913850849@sourceware.org> Date: Mon, 13 Jun 2022 21:55:12 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 13 Jun 2022 21:55:12 -0000 https://gcc.gnu.org/g:2c11662391bafd74c9d19bf7626b7bcef41c1323 commit r13-1076-g2c11662391bafd74c9d19bf7626b7bcef41c1323 Author: Jason Merrill Date: Fri Jun 10 15:26:36 2022 -0400 ubsan: -Wreturn-type and ubsan trap-on-error I noticed that -fsanitize=undefined -fsanitize-undefined-trap-on-error was omitting the usual -Wreturn-type warning for control flowing off the end of a function. This was because the warning code was looking for calls either to __builtin_unreachable or the UBSan function, but these flags produce a call to __builtin_trap instead. gcc/c-family/ChangeLog: * c-ubsan.cc (ubsan_instrument_return): Use BUILTINS_LOCATION. gcc/ChangeLog: * tree-cfg.cc (pass_warn_function_return::execute): Also check BUILT_IN_TRAP. gcc/testsuite/ChangeLog: * g++.dg/ubsan/return-8.C: New test. Diff: --- gcc/c-family/c-ubsan.cc | 4 +++- gcc/testsuite/g++.dg/ubsan/return-8.C | 9 +++++++++ gcc/tree-cfg.cc | 5 +++-- 3 files changed, 15 insertions(+), 3 deletions(-) diff --git a/gcc/c-family/c-ubsan.cc b/gcc/c-family/c-ubsan.cc index 48f948745f8..a2cd8fb3262 100644 --- a/gcc/c-family/c-ubsan.cc +++ b/gcc/c-family/c-ubsan.cc @@ -308,7 +308,9 @@ tree ubsan_instrument_return (location_t loc) { if (flag_sanitize_undefined_trap_on_error) - return build_call_expr_loc (loc, builtin_decl_explicit (BUILT_IN_TRAP), 0); + return build_call_expr_loc + /* pass_warn_function_return checks for BUILTINS_LOCATION. */ + (BUILTINS_LOCATION, builtin_decl_explicit (BUILT_IN_TRAP), 0); tree data = ubsan_create_data ("__ubsan_missing_return_data", 1, &loc, NULL_TREE, NULL_TREE); diff --git a/gcc/testsuite/g++.dg/ubsan/return-8.C b/gcc/testsuite/g++.dg/ubsan/return-8.C new file mode 100644 index 00000000000..354c96098d2 --- /dev/null +++ b/gcc/testsuite/g++.dg/ubsan/return-8.C @@ -0,0 +1,9 @@ +// { dg-additional-options "-fsanitize=undefined -fsanitize-undefined-trap-on-error" } + +bool b; + +int f() { + if (b) return 42; +} // { dg-warning "-Wreturn-type" } + +int main() { f(); } diff --git a/gcc/tree-cfg.cc b/gcc/tree-cfg.cc index 9e5d84a9805..c67c278dad0 100644 --- a/gcc/tree-cfg.cc +++ b/gcc/tree-cfg.cc @@ -9543,7 +9543,7 @@ pass_warn_function_return::execute (function *fun) } /* The C++ FE turns fallthrough from the end of non-void function into __builtin_unreachable () call with BUILTINS_LOCATION. - Recognize those too. */ + Recognize those as well as calls from ubsan_instrument_return. */ basic_block bb; if (!warning_suppressed_p (fun->decl, OPT_Wreturn_type)) FOR_EACH_BB_FN (bb, fun) @@ -9555,7 +9555,8 @@ pass_warn_function_return::execute (function *fun) if (last && ((LOCATION_LOCUS (gimple_location (last)) == BUILTINS_LOCATION - && gimple_call_builtin_p (last, BUILT_IN_UNREACHABLE)) + && (gimple_call_builtin_p (last, BUILT_IN_UNREACHABLE) + || gimple_call_builtin_p (last, BUILT_IN_TRAP))) || gimple_call_builtin_p (last, ubsan_missing_ret))) { gimple_stmt_iterator gsi = gsi_for_stmt (last);