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
2013-07-27 Tobias Burnus <bur...@net-b.de>
PR fortran/57991
* interface.c (check_some_aliasing): Also warn for intent OUT/OUT.
2013-07-27 Tobias Burnus <bur...@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
+
