* decl.c (start_enum): Do compare dependent underlying type.

From-SVN: r261655

gcc/cp/ChangeLog

 2018-06-15  Jason Merrill  <jason@redhat.com>
 
+	* decl.c (start_enum): Do compare dependent underlying type.
+
 	PR c++/82882 - ICE with lambda in template default argument.
 	* lambda.c (record_null_lambda_scope): New.
 	* pt.c (tsubst_lambda_expr): Use it.

gcc/cp/decl.c

@@ -14131,8 +14131,6 @@ start_enum (tree name, tree enumtype, tree underlying_type,
 	  enumtype = error_mark_node;
 	}
       else if (underlying_type && ENUM_UNDERLYING_TYPE (enumtype)
-	       && !dependent_type_p (underlying_type)
-	       && !dependent_type_p (ENUM_UNDERLYING_TYPE (enumtype))
 	       && !same_type_p (underlying_type,
 				ENUM_UNDERLYING_TYPE (enumtype)))
 	{
@@ -14157,7 +14155,7 @@ start_enum (tree name, tree enumtype, tree underlying_type,
 
       /* enumtype may be an ENUMERAL_TYPE if this is a redefinition
          of an opaque enum, or an opaque enum of an already defined
-	 enumeration (C++0x only).
+	 enumeration (C++11).
 	 In any other case, it'll be NULL_TREE. */
       if (!enumtype)
 	{
@@ -14166,14 +14164,9 @@ start_enum (tree name, tree enumtype, tree underlying_type,
 	}
       prevtype = enumtype;
 
-      /* Do not push the decl more than once, unless we need to
-	 compare underlying types at instantiation time */
+      /* Do not push the decl more than once.  */
       if (!enumtype
-	  || TREE_CODE (enumtype) != ENUMERAL_TYPE
-	  || (underlying_type
-	      && dependent_type_p (underlying_type))
-	  || (ENUM_UNDERLYING_TYPE (enumtype)
-	      && dependent_type_p (ENUM_UNDERLYING_TYPE (enumtype))))
+	  || TREE_CODE (enumtype) != ENUMERAL_TYPE)
 	{
 	  enumtype = cxx_make_type (ENUMERAL_TYPE);
 	  enumtype = pushtag (name, enumtype, /*tag_scope=*/ts_current);

gcc/cp/name-lookup.h

@@ -112,7 +112,7 @@ enum scope_kind {
 			of an if or switch statement.  */
   sk_function_parms, /* The scope containing function parameters.  */
   sk_class,	     /* The scope containing the members of a class.  */
-  sk_scoped_enum,    /* The scope containing the enumertors of a C++0x
+  sk_scoped_enum,    /* The scope containing the enumerators of a C++11
                         scoped enumeration.  */
   sk_namespace,	     /* The scope containing the members of a
 			namespace, including the global scope.  */

gcc/testsuite/g++.dg/cpp0x/forw_enum10.C

@@ -6,7 +6,7 @@ template<typename T> struct S1
     enum E : T;   // { dg-message "previous definition" }
     enum E : int;     // { dg-error "different underlying type" }
 };
-template struct S1<short>; // { dg-message "required from here" }
+template struct S1<short>;
 
 template<typename T> struct S2
 {
@@ -17,8 +17,8 @@ template struct S2<short>;
 
 template<typename T1, typename T2> struct S3
 {
-    enum E : T1;
-    enum E : T2;
+    enum E : T1;		// { dg-message "previous definition" }
+    enum E : T2;		// { dg-error "different underlying type" }
 };
 template struct S3<short,short>;
 
@@ -27,4 +27,4 @@ template<typename T1, typename T2> struct S4
     enum E : T1; // { dg-message "previous definition" }
     enum E : T2; // { dg-error "different underlying type" }
 };
-template struct S4<short,char>; // { dg-message "required from here" }
+template struct S4<short,char>;

gcc/testsuite/g++.dg/cpp0x/forw_enum7.C

@@ -4,8 +4,6 @@
 template<typename T> struct S1
 {
     enum E1 : int;
-    enum E1 : T;
-    enum class E2 : int;
     enum class E2 : T;
 };
 

gcc/testsuite/g++.dg/cpp0x/forw_enum8.C

 // { dg-do compile { target c++11 } }
 
-//This instatiation is ok
 template<typename T> struct S1
 {
-    enum E : int;
-    enum E : T;
+    enum E : int;   // { dg-message "previous definition" }
+    enum E : T;     // { dg-error "different underlying type" }
 };
 template struct S1<int>; //ok
 
-//This error is diagnosed at instantiation time
 template<typename T> struct S2
 {
     enum E : int;   // { dg-message "previous definition" }
     enum E : T;     // { dg-error "different underlying type" }
 };
-template struct S2<short>; // { dg-message "required from here" }
+template struct S2<short>;
 
-//This error is diagnosed at compilation time
 template<typename T> struct S3
 {
     enum E : int;   // { dg-message "previous definition" }