| Message ID | mptftn6bbxk.fsf@arm.com |
|---|---|
| State | New |
| Headers | show |
| Series | Fix -Wreturn-type for static naked functions in C | expand |
On Tue, Jul 16, 2019 at 09:50:31AM +0100, Richard Sandiford wrote: > This patch extends the fix for PR53633 to include static functions, > which were giving a bogus -Wreturn-type warning for C but not for C++. > > Tested on aarch64-linux-gnu, x86_64-linux-gnu and armeb-eabi. > OK for trunk? OK for GCC 8 and 9 too? I don't think it's > a regression, but the current behaviour's very inconsistent > and it's affecting real code. Ok, thanks. > 2019-07-16 Richard Sandiford <richard.sandiford@arm.com> > > gcc/c/ > PR c/53633 > * c-decl.c (finish_function): Check targetm.warn_func_return > before issuing a -Wreturn-type warning. > > gcc/testsuite/ > * c-c++-common/pr53633-2.c: New test. > > Index: gcc/c/c-decl.c > =================================================================== > --- gcc/c/c-decl.c 2019-07-10 19:41:20.543944894 +0100 > +++ gcc/c/c-decl.c 2019-07-16 09:46:23.220645712 +0100 > @@ -9687,6 +9687,7 @@ finish_function (void) > /* Normally, with -Wreturn-type, flow will complain, but we might > optimize out static functions. */ > && !TREE_PUBLIC (fndecl) > + && targetm.warn_func_return (fndecl) > && warning (OPT_Wreturn_type, > "no return statement in function returning non-void")) > TREE_NO_WARNING (fndecl) = 1; > Index: gcc/testsuite/c-c++-common/pr53633-2.c > =================================================================== > --- /dev/null 2019-06-14 15:59:19.298479944 +0100 > +++ gcc/testsuite/c-c++-common/pr53633-2.c 2019-07-16 09:46:23.220645712 +0100 > @@ -0,0 +1,19 @@ > +/* { dg-do compile } */ > +/* { dg-require-effective-target naked_functions } */ > +/* { dg-options "-O2 -Wall" } */ > +/* Check that we do not get warnings about missing return statements > + or bogus looking noreturn functions. */ > +static int __attribute__((naked)) > +foo (void) > +{ > + __asm__ (""); > +} > + > +static int __attribute__((naked,noreturn)) > +bar (void) > +{ > + __asm__ (""); > +} > + > +int foo_caller (void) { return foo (); } > +int bar_caller (void) { return bar (); } Marek
Index: gcc/c/c-decl.c =================================================================== --- gcc/c/c-decl.c 2019-07-10 19:41:20.543944894 +0100 +++ gcc/c/c-decl.c 2019-07-16 09:46:23.220645712 +0100 @@ -9687,6 +9687,7 @@ finish_function (void) /* Normally, with -Wreturn-type, flow will complain, but we might optimize out static functions. */ && !TREE_PUBLIC (fndecl) + && targetm.warn_func_return (fndecl) && warning (OPT_Wreturn_type, "no return statement in function returning non-void")) TREE_NO_WARNING (fndecl) = 1; Index: gcc/testsuite/c-c++-common/pr53633-2.c =================================================================== --- /dev/null 2019-06-14 15:59:19.298479944 +0100 +++ gcc/testsuite/c-c++-common/pr53633-2.c 2019-07-16 09:46:23.220645712 +0100 @@ -0,0 +1,19 @@ +/* { dg-do compile } */ +/* { dg-require-effective-target naked_functions } */ +/* { dg-options "-O2 -Wall" } */ +/* Check that we do not get warnings about missing return statements + or bogus looking noreturn functions. */ +static int __attribute__((naked)) +foo (void) +{ + __asm__ (""); +} + +static int __attribute__((naked,noreturn)) +bar (void) +{ + __asm__ (""); +} + +int foo_caller (void) { return foo (); } +int bar_caller (void) { return bar (); }