diff mbox

[Fortran] PR57991 - add alias warning for intent(out)/intent(out)

Message ID 51F3B00A.8010205@net-b.de
State New
Headers show

Commit Message

Tobias Burnus July 27, 2013, 11:33 a.m. UTC 
Passing the same argument to nonpointer dummy arguments is only 
permitted if one does not modify the values.

gfortran was warning for intent(in)/intent(out) and for OUT/IN but not 
for OUT/OUT. This patch now also warns for the latter.

Build and regtested on x86-64-gnu-linux.
OK for the trunk?

Tobias

Comments

Thomas Koenig July 27, 2013, 11:37 a.m. UTC | #1 
Hi Tobias,

> Passing the same argument to nonpointer dummy arguments is only
> permitted if one does not modify the values.
>
> gfortran was warning for intent(in)/intent(out) and for OUT/IN but not
> for OUT/OUT. This patch now also warns for the latter.
>
> Build and regtested on x86-64-gnu-linux.
> OK for the trunk?

OK (obvious really).

Thanks for the patch!

	Thomas
diff mbox

Patch

2013-07-27  Tobias Burnus  <burnus@net-b.de>

	PR fortran/57991
	* interface.c (check_some_aliasing): Also warn for intent OUT/OUT.

2013-07-27  Tobias Burnus  <burnus@net-b.de>

	PR fortran/57991
	* gfortran.dg/warn_alias.f90: New.

diff --git a/gcc/fortran/interface.c b/gcc/fortran/interface.c
index 3c794b2..606cef5 100644
--- a/gcc/fortran/interface.c
+++ b/gcc/fortran/interface.c
@@ -3078,7 +3079,8 @@  check_some_aliasing (gfc_formal_arglist *f, gfc_actual_arglist *a)
 	    break;
 	  f2_intent = p[j].f->sym->attr.intent;
 	  if ((f1_intent == INTENT_IN && f2_intent == INTENT_OUT)
-	      || (f1_intent == INTENT_OUT && f2_intent == INTENT_IN))
+	      || (f1_intent == INTENT_OUT && f2_intent == INTENT_IN)
+	      || (f1_intent == INTENT_OUT && f2_intent == INTENT_OUT))
 	    {
 	      gfc_warning ("Same actual argument associated with INTENT(%s) "
 			   "argument '%s' and INTENT(%s) argument '%s' at %L",
--- /dev/null	2013-07-27 10:10:46.283765931 +0200
+++ gcc/gcc/testsuite/gfortran.dg/warn_alias.f90	2013-07-27 13:06:05.221802513 +0200
@@ -0,0 +1,33 @@ 
+! { dg-do compile }
+! { dg-options "-Waliasing" }
+!
+! PR fortran/57991
+!
+! Added check for OUT/OUT. IN/OUT and OUT/IN where already check
+! since GCC 4.0, but not being tested for.
+
+      Program q
+        integer :: x
+        x = 5
+        Call test1(x, x) ! { dg-warning "Same actual argument associated with INTENT.OUT. argument 'a' and INTENT.OUT. argument 'b'" }
+        Call test2(x, x) ! { dg-warning "Same actual argument associated with INTENT.IN. argument 'a' and INTENT.OUT. argument 'b'" }
+        Call test3(x, x) ! { dg-warning "Same actual argument associated with INTENT.OUT. argument 'a' and INTENT.IN. argument 'b'" }
+      Contains
+        Subroutine test1(a,b)
+          Integer, intent(out) :: a
+          Integer, intent(out) :: b
+          b = 5
+          a = 5
+        End Subroutine
+        Subroutine test2(a,b)
+          Integer, intent(in) :: a
+          Integer, intent(out) :: b
+          b = 5 + a
+        End Subroutine
+        Subroutine test3(a,b)
+          Integer, intent(out) :: a
+          Integer, intent(in) :: b
+          a = 5 + b
+        End Subroutine
+      End Program
+