From 4ea128d5c740e4e8c2e7b70de3a90435035eb863 Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Wed, 9 Mar 2022 22:51:23 +0000 Subject: [PATCH] c: Revert C2x changes to function type compatibility In commit cc806126215c3f4dc187eff3bf923458d8cc6b4f, I implemented changes that C2x had made to compatibility of unprototyped and prototyped function types. C2x has since completely removed unprototyped function types, making () in a function declaration mean (void) as in C++. While that change isn't appropriate at the current development stage for GCC 12, it does mean that it doesn't make sense for GCC 12 to have different rules for unprototyped functions in C2x mode than in other modes or previous and subsequent GCC versions. Thus, revert the previous change to avoid it getting into a GCC release, and update the corresponding tests to expect the same behavior with -std=c2x as with -std=c11 (they will of course need to change again after implementing () as meaning (void)). Bootstrapped with no regressions for x86_64-pc-linux-gnu. gcc/c/ * c-typeck.cc (function_types_compatible_p): Do not handle C2X differently from earlier standards for unprototyped function type compatibility. gcc/testsuite/ * gcc.dg/c11-unproto-1.c, gcc.dg/c11-unproto-2.c: Update comments. * gcc.dg/c2x-unproto-1.c, gcc.dg/c2x-unproto-2.c: Expect same results as in C11 mode. Update comments. --- gcc/c/c-typeck.cc | 4 ++-- gcc/testsuite/gcc.dg/c11-unproto-1.c | 7 ++++--- gcc/testsuite/gcc.dg/c11-unproto-2.c | 7 ++++--- gcc/testsuite/gcc.dg/c2x-unproto-1.c | 29 +++++++++++++++++------------ gcc/testsuite/gcc.dg/c2x-unproto-2.c | 7 ++++--- 5 files changed, 31 insertions(+), 23 deletions(-) diff --git a/gcc/c/c-typeck.cc b/gcc/c/c-typeck.cc index b37f3cf..54b0b0d 100644 --- a/gcc/c/c-typeck.cc +++ b/gcc/c/c-typeck.cc @@ -1693,7 +1693,7 @@ function_types_compatible_p (const_tree f1, const_tree f2, if (args1 == NULL_TREE) { - if (flag_isoc2x ? stdarg_p (f2) : !self_promoting_args_p (args2)) + if (!self_promoting_args_p (args2)) return 0; /* If one of these types comes from a non-prototype fn definition, compare that with the other type's arglist. @@ -1706,7 +1706,7 @@ function_types_compatible_p (const_tree f1, const_tree f2, } if (args2 == NULL_TREE) { - if (flag_isoc2x ? stdarg_p (f1) : !self_promoting_args_p (args1)) + if (!self_promoting_args_p (args1)) return 0; if (TYPE_ACTUAL_ARG_TYPES (f2) && type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2), diff --git a/gcc/testsuite/gcc.dg/c11-unproto-1.c b/gcc/testsuite/gcc.dg/c11-unproto-1.c index ea9e807..0949c7b 100644 --- a/gcc/testsuite/gcc.dg/c11-unproto-1.c +++ b/gcc/testsuite/gcc.dg/c11-unproto-1.c @@ -1,6 +1,7 @@ -/* Test compatibility of unprototyped and prototyped function types (C2x makes - the case of types affected by default argument promotions compatible). Test - valid-in-C2x usages are not accepted for C11. */ +/* Test compatibility of unprototyped and prototyped function types (C2x made + the case of types affected by default argument promotions compatible, before + removing unprototyped functions completely). Test affected usages are not + accepted for C11. */ /* { dg-do compile } */ /* { dg-options "-std=c11 -pedantic-errors" } */ diff --git a/gcc/testsuite/gcc.dg/c11-unproto-2.c b/gcc/testsuite/gcc.dg/c11-unproto-2.c index 0557ae3..06da935 100644 --- a/gcc/testsuite/gcc.dg/c11-unproto-2.c +++ b/gcc/testsuite/gcc.dg/c11-unproto-2.c @@ -1,6 +1,7 @@ -/* Test compatibility of unprototyped and prototyped function types (C2x makes - the case of types affected by default argument promotions compatible). Test - invalid-in-C2x usages, in C11 mode. */ +/* Test compatibility of unprototyped and prototyped function types (C2x made + the case of types affected by default argument promotions compatible, before + removing unprototyped functions completely). Test always-invalid-in-C2x + usages, in C11 mode. */ /* { dg-do compile } */ /* { dg-options "-std=c11 -pedantic-errors" } */ diff --git a/gcc/testsuite/gcc.dg/c2x-unproto-1.c b/gcc/testsuite/gcc.dg/c2x-unproto-1.c index 45d68f2..aa87d78 100644 --- a/gcc/testsuite/gcc.dg/c2x-unproto-1.c +++ b/gcc/testsuite/gcc.dg/c2x-unproto-1.c @@ -1,20 +1,25 @@ -/* Test compatibility of unprototyped and prototyped function types (C2x makes - the case of types affected by default argument promotions compatible). Test - valid-in-C2x usages. */ +/* Test compatibility of unprototyped and prototyped function types (C2x made + the case of types affected by default argument promotions compatible, before + removing unprototyped functions completely). Test affected usages are not + accepted for C2x. */ /* { dg-do compile } */ /* { dg-options "-std=c2x -pedantic-errors" } */ -void f1 (); -void f1 (float); +void f1 (); /* { dg-message "previous declaration" } */ +void f1 (float); /* { dg-error "conflicting types" } */ +/* { dg-message "default promotion" "" { target *-*-* } .-1 } */ -void f2 (float); -void f2 (); +void f2 (float); /* { dg-message "previous declaration" } */ +void f2 (); /* { dg-error "conflicting types" } */ +/* { dg-message "default promotion" "" { target *-*-* } .-1 } */ -void f3 (); -void f3 (char); +void f3 (); /* { dg-message "previous declaration" } */ +void f3 (char); /* { dg-error "conflicting types" } */ +/* { dg-message "default promotion" "" { target *-*-* } .-1 } */ -void f4 (char); -void f4 (); +void f4 (char); /* { dg-message "previous declaration" } */ +void f4 (); /* { dg-error "conflicting types" } */ +/* { dg-message "default promotion" "" { target *-*-* } .-1 } */ /* Built-in function case. */ -float sqrtf (); +float sqrtf (); /* { dg-warning "conflicting types for built-in function" } */ diff --git a/gcc/testsuite/gcc.dg/c2x-unproto-2.c b/gcc/testsuite/gcc.dg/c2x-unproto-2.c index f826b7c..3d5ae9d 100644 --- a/gcc/testsuite/gcc.dg/c2x-unproto-2.c +++ b/gcc/testsuite/gcc.dg/c2x-unproto-2.c @@ -1,6 +1,7 @@ -/* Test compatibility of unprototyped and prototyped function types (C2x makes - the case of types affected by default argument promotions compatible). Test - invalid-in-C2x usages. */ +/* Test compatibility of unprototyped and prototyped function types (C2x made + the case of types affected by default argument promotions compatible, before + removing unprototyped functions completely). Test always-invalid-in-C2x + usages, in C2X mode. */ /* { dg-do compile } */ /* { dg-options "-std=c2x -pedantic-errors" } */ -- 2.7.4