re PR fortran/77420 (gfortran and equivalence produces internal compiler error)

2016-09-09  Steven G. Kargl  <kargl@gcc.gnu.org>

	PR fortran/77420
	* module.c (load_equiv): If the current namespace has a list of
	equivalence statements, initialize duplicate to false and then
	look for duplicates; otherwise, initialize it to true.
 
2016-09-09  Steven G. Kargl  <kargl@gcc.gnu.org>

	PR fortran/77420
	* gfortran.dg/pr77420.f90: New test.

From-SVN: r240063

gcc/fortran/module.c

@@ -4647,7 +4647,7 @@ load_equiv (void)
       }
 
     /* Check for duplicate equivalences being loaded from different modules */
-    duplicate = false;
+    duplicate = gfc_current_ns->equiv ? false:true;
     for (equiv = gfc_current_ns->equiv; equiv; equiv = equiv->next)
       {
 	if (equiv->module && head->module

gcc/testsuite/ChangeLog

+2016-09-09  Steven G. Kargl  <kargl@gcc.gnu.org>
+
+	PR fortran/77420
+	* module.c (load_equiv): If the current namespace has a list of
+	equivalence statements, initialize duplicate to false and then
+	look for duplicates; otherwise, initialize it to true.
+
 2016-09-09  Martin Sebor  <msebor@redhat.com>
 
 	PR c/77520
@@ -7,6 +14,11 @@
 
 2016-09-09  Steven G. Kargl  <kargl@gcc.gnu.org>
 
+	PR fortran/77420
+	* gfortran.dg/pr77420.f90: New test.
+
+2016-09-09  Steven G. Kargl  <kargl@gcc.gnu.org>
+
 	PR fortran/77506
 	* gfortran.dg/pr77506.f90: New test.
 

gcc/testsuite/gfortran.dg/pr77420.f90

+! { dg-do compile }
+MODULE test_equivalence
+  REAL, PRIVATE, DIMENSION(100) :: array1
+  REAL, PRIVATE, DIMENSION(100) :: array2
+  EQUIVALENCE(array1(1),array2(1))
+END MODULE test_equivalence
+
+MODULE mymodule
+  USE test_equivalence
+  ! declare a local variable with the same name as the (private!)
+  ! variable in module test_equivalence:
+  REAL, DIMENSION(:), ALLOCATABLE :: array1
+END MODULE mymodule
+
+PROGRAM test
+  USE mymodule
+END PROGRAM test
+