Index: fortran/resolve.c
===================================================================
--- fortran/resolve.c	(revision 246143)
+++ fortran/resolve.c	(working copy)
@@ -15560,7 +15560,7 @@ resolve_equivalence (gfc_equiv *eq)
   locus *last_where = NULL;
   seq_type eq_type, last_eq_type;
   gfc_typespec *last_ts;
-  int object, cnt_protected;
+  int object, cnt_protected, cnt_volatile;
   const char *msg;
 
   last_ts = &eq->expr->symtree->n.sym->ts;
@@ -15569,6 +15569,8 @@ resolve_equivalence (gfc_equiv *eq)
 
   cnt_protected = 0;
 
+  cnt_volatile = 0;
+
   for (object = 1; eq; eq = eq->eq, object++)
     {
       e = eq->expr;
@@ -15641,6 +15643,17 @@ resolve_equivalence (gfc_equiv *eq)
 
       sym = e->symtree->n.sym;
 
+      if(sym->attr.volatile_)
+        cnt_volatile++;
+      if(cnt_volatile > 0 && cnt_volatile != object)
+	{
+	  gfc_warning (0, "Either all or none of the objects in "
+	  	       "the EQUIVALENCE set at %L should have the "
+		       "VOLATILE attribute",
+		       &e->where);
+	  break;
+	}
+
       if (sym->attr.is_protected)
 	cnt_protected++;
       if (cnt_protected > 0 && cnt_protected != object)
Index: testsuite/gfortran.dg/volatile11.f90
===================================================================
--- testsuite/gfortran.dg/volatile11.f90	(revision 246140)
+++ testsuite/gfortran.dg/volatile11.f90	(working copy)
@@ -3,6 +3,7 @@
 ! Tests that volatile can be applied to members of common blocks or
 ! equivalence groups (PR fortran/35037)
 !
+
 subroutine wait1
   logical event
   volatile event
@@ -16,7 +17,7 @@ end subroutine
 subroutine wait2
   logical event, foo
   volatile event
-  equivalence (event, foo)
+  equivalence (event, foo) ! { dg-warning "in the EQUIVALENCE set" }
   event = .false.
   do
     if (event) print *, 'NotOptimizedAway2'
@@ -27,7 +28,7 @@ subroutine wait3
   logical event
   integer foo
   volatile foo
-  equivalence (event, foo)
+  equivalence (event, foo) ! { dg-warning "in the EQUIVALENCE set" }
   event = .false.
   do
     if (event) print *, 'IsOptimizedAway'