re PR fortran/89646 (Spurious actual argument might interfere warning)

2019-06-14  Steven G. Kargl  <kargl@gcc.gnu.org>

	PR fortran/89646
	* dependency.c (gfc_check_argument_var_dependency): Suppress spurious
	warnings by comparing variable names.

2019-06-14  Steven G. Kargl  <kargl@gcc.gnu.org>

	PR fortran/89646
	* gfortran.dg/pr89646.f90: New test.

From-SVN: r272307

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 99a399a..9a82b9b 100644 (file)
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,4 +1,10 @@
-2019-06-12  Steven G. Kargl  <kargl@gcc.gnu.org>
+2019-06-14  Steven G. Kargl  <kargl@gcc.gnu.org>
+
+       PR fortran/89646
+       * dependency.c (gfc_check_argument_var_dependency): Suppress spurious
+       warnings by comparing variable names.
+
+2019-06-13  Steven G. Kargl  <kargl@gcc.gnu.org>
 
        PR fortran/68544
        * resolve.c (is_dt_name): New function to compare symbol name against

diff --git a/gcc/fortran/dependency.c b/gcc/fortran/dependency.c
index 8eae644..be330e2 100644 (file)
--- a/gcc/fortran/dependency.c
+++ b/gcc/fortran/dependency.c
@@ -979,10 +979,14 @@ gfc_check_argument_var_dependency (gfc_expr *var, sym_intent intent,
                     If a dependency is found in the case
                     elemental == ELEM_CHECK_VARIABLE, we will generate
                     a temporary, so we don't need to bother the user.  */
-                 gfc_warning (0, "INTENT(%s) actual argument at %L might "
-                              "interfere with actual argument at %L.",
-                              intent == INTENT_OUT ? "OUT" : "INOUT",
-                              &var->where, &expr->where);
+
+                 if (var->expr_type == EXPR_VARIABLE
+                     && expr->expr_type == EXPR_VARIABLE
+                     && strcmp(var->symtree->name, expr->symtree->name) == 0)
+                   gfc_warning (0, "INTENT(%s) actual argument at %L might "
+                                "interfere with actual argument at %L.",
+                                intent == INTENT_OUT ? "OUT" : "INOUT",
+                                &var->where, &expr->where);
                }
              return 0;
            }

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 3d64fb0..8ab6cb4 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-06-14  Steven G. Kargl  <kargl@gcc.gnu.org>
+
+       PR fortran/89646
+       * gfortran.dg/pr89646.f90: New test.
+
 2019-06-14  H.J. Lu  <hongjiu.lu@intel.com>
 
        PR rtl-optimization/90765

diff --git a/gcc/testsuite/gfortran.dg/pr89646.f90 b/gcc/testsuite/gfortran.dg/pr89646.f90
new file mode 100644 (file)
index 0000000..c348020
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/pr89646.f90
@@ -0,0 +1,24 @@
+! { dg-do compile }
+! PR fortran/89646
+! Original testcase contributed by Ian Harvey <ian_harvey at bigpond dot com>
+!
+! This code use to give spurious warnings about aliasing.
+!
+module m
+   implicit none
+   type :: t
+   end type t
+   contains
+      ! To reproduce, both actual arguments must be TARGET, 
+      ! both arguments must be of derived type.
+      subroutine s
+         type(t), target :: a(5)
+         type(t), target :: b(5)
+         call move(a, b)
+      end subroutine s
+      ! To reproduce, called procedure must be elemental.
+      elemental subroutine move(x, y)
+         type(t), intent(inout) :: x
+         type(t), intent(out) :: y
+      end subroutine move
+end module m