Don't make unsized objects into extern.

2018-08-15  Iain Sandoe <iain@sandoe.co.uk>

gcc/c:

        PR c/19315
        * c-decl.c (finish_decl): Don't add the 'extern' storage class to
        objects of unknown size.

gcc/testsuite:

        PR c/19315
        gcc.dg/graphite/pr82451.c: Make array 'a' an extern.
        gcc.dg/redecl-10.c: Expect warnings for the static vars with unknown
        size.

From-SVN: r263556

gcc/c/ChangeLog

+2018-08-15  Iain Sandoe  <iain@sandoe.co.uk>
+
+	PR c/19315
+	* c-decl.c (finish_decl): Don't add the 'extern' storage class to
+	objects of unknown size.
+
 2018-08-13  Martin Sebor  <msebor@redhat.com>
 
 	PR tree-optimization/71625

gcc/c/c-decl.c

@@ -4969,14 +4969,6 @@ finish_decl (tree decl, location_t init_loc, tree init,
 	case 2:
 	  if (do_default)
 	    error ("array size missing in %q+D", decl);
-	  /* If a `static' var's size isn't known,
-	     make it extern as well as static, so it does not get
-	     allocated.
-	     If it is not `static', then do not mark extern;
-	     finish_incomplete_decl will give it a default size
-	     and it will get allocated.  */
-	  else if (!pedantic && TREE_STATIC (decl) && !TREE_PUBLIC (decl))
-	    DECL_EXTERNAL (decl) = 1;
 	  break;
 
 	case 3:

gcc/testsuite/ChangeLog

+2018-08-15  Iain Sandoe  <iain@sandoe.co.uk>
+
+	PR c/19315
+	* gcc.dg/graphite/pr82451.c: Make array 'a' an extern.
+	* gcc.dg/redecl-10.c: Expect warnings for the static vars with
+	unknown size.
+
 2018-08-15  Martin Liska  <mliska@suse.cz>
 
         PR tree-optimization/86925

gcc/testsuite/gcc.dg/graphite/pr82451.c

 /* { dg-do compile } */
 /* { dg-options "-O -floop-parallelize-all" } */
 
-static int a[];
+extern int a[];
 int b[1];
 int c;
 static void

gcc/testsuite/gcc.dg/redecl-10.c

@@ -5,7 +5,7 @@
 /* { dg-do compile } */
 /* { dg-options "-g" } */
 
-static int w[];
+static int w[]; /* { dg-warning "array 'w' assumed to have one element" } */
 void
 f (void)
 {
@@ -19,7 +19,7 @@ g (void)
   extern int x[] = { 3, 4, 5 }; /* { dg-error "has both" } */
 }
 
-static int y[];
+static int y[]; /* { dg-warning "array 'y' assumed to have one element" } */
 void
 h (void)
 {