re PR c/63543 (incomplete type error should suppress duplicates)

	PR c/63543
	* c-tree.h (C_TYPE_ERROR_REPORTED): Define.
	* c-typeck.c (build_indirect_ref): Don't print the "dereferencing..."
	error multiple times.  Print the type.

	* gcc.dg/pr63543.c: New test.
	* gcc.dg/array-8.c: Remove dg-error.
	* gcc.dg/pr48552-1.c: Remove and adjust dg-error.
	* gcc.dg/pr48552-2.c: Likewise.

From-SVN: r216414

gcc/c/ChangeLog

 2014-10-17  Marek Polacek  <polacek@redhat.com>
 
+	PR c/63543
+	* c-tree.h (C_TYPE_ERROR_REPORTED): Define.
+	* c-typeck.c (build_indirect_ref): Don't print the "dereferencing..."
+	error multiple times.  Print the type.
+
+2014-10-17  Marek Polacek  <polacek@redhat.com>
+
 	PR c/63549
 	* c-typeck.c (build_array_ref): Bail if the index in an incomplete
 	type.

gcc/c/c-tree.h

@@ -56,6 +56,9 @@ along with GCC; see the file COPYING3.  If not see
    This is used for -Wc++-compat. */
 #define C_TYPE_DEFINED_IN_STRUCT(TYPE) TYPE_LANG_FLAG_2 (TYPE)
 
+/* Record whether an "incomplete type" error was given for the type.  */
+#define C_TYPE_ERROR_REPORTED(TYPE) TYPE_LANG_FLAG_3 (TYPE)
+
 /* Record whether a typedef for type `int' was actually `signed int'.  */
 #define C_TYPEDEF_EXPLICITLY_SIGNED(EXP) DECL_LANG_FLAG_1 (EXP)
 

gcc/c/c-typeck.c

@@ -2378,7 +2378,12 @@ build_indirect_ref (location_t loc, tree ptr, ref_operator errstring)
 
 	  if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
 	    {
-	      error_at (loc, "dereferencing pointer to incomplete type");
+	      if (!C_TYPE_ERROR_REPORTED (TREE_TYPE (ptr)))
+		{
+		  error_at (loc, "dereferencing pointer to incomplete type "
+			    "%qT", t);
+		  C_TYPE_ERROR_REPORTED (TREE_TYPE (ptr)) = 1;
+		}
 	      return error_mark_node;
 	    }
 	  if (VOID_TYPE_P (t) && c_inhibit_evaluation_warnings == 0)

gcc/testsuite/ChangeLog

 2014-10-17  Marek Polacek  <polacek@redhat.com>
 
+	PR c/63543
+	* gcc.dg/pr63543.c: New test.
+	* gcc.dg/array-8.c: Remove dg-error.
+	* gcc.dg/pr48552-1.c: Remove and adjust dg-error.
+	* gcc.dg/pr48552-2.c: Likewise.
+
+2014-10-17  Marek Polacek  <polacek@redhat.com>
+
 	PR c/63549
 	* gcc.dg/pr63549.c: New test.
 

gcc/testsuite/gcc.dg/array-8.c

@@ -45,5 +45,4 @@ g (void)
   sip[0]; /* { dg-error "invalid use of undefined type 'struct si'" } */
   /* { dg-error "dereferencing pointer to incomplete type" "incomplete" { target *-*-* } 45 } */
   0[sip]; /* { dg-error "invalid use of undefined type 'struct si'" } */
-  /* { dg-error "dereferencing pointer to incomplete type" "incomplete" { target *-*-* } 47 } */
 }

gcc/testsuite/gcc.dg/pr48552-1.c

@@ -49,5 +49,5 @@ f7 (struct S *x)
 void
 f8 (struct S *x)
 {
-  __asm volatile ("" : "=r" (*x));	/* { dg-error "dereferencing pointer to incomplete type" "incomplete" } */
-}					/* { dg-error "invalid lvalue in asm output 0" "invalid lvalue" { target *-*-* } 52 } */
+  __asm volatile ("" : "=r" (*x));	/* { dg-error "invalid lvalue in asm output 0" } */
+}

gcc/testsuite/gcc.dg/pr48552-2.c

@@ -49,5 +49,5 @@ f7 (struct S *x)
 void
 f8 (struct S *x)
 {
-  __asm ("" : "=r" (*x));	/* { dg-error "dereferencing pointer to incomplete type" "incomplete" } */
-}				/* { dg-error "invalid lvalue in asm output 0" "invalid lvalue" { target *-*-* } 52 } */
+  __asm ("" : "=r" (*x));	/* { dg-error "invalid lvalue in asm output 0" } */
+}

gcc/testsuite/gcc.dg/pr63543.c

+/* PR c/63543 */
+/* { dg-do compile } */
+
+struct S;
+union U;
+
+int
+f1 (struct S *s)
+{
+  return s->a /* { dg-error "dereferencing pointer to incomplete type .struct S." } */
+	 + s->b
+	 + s->c;
+}
+
+int
+f2 (union U *u)
+{
+  return u->a /* { dg-error "dereferencing pointer to incomplete type .union U." } */
+	 + u->a
+	 + u->a;
+}