[PATCH PR C++/58781, 59867, 60249 ] Various user-defined string literal issues involving character encodings, dropped bytes, semi-infinite loops

[Ed Smith-Rowland]

Please disregard previous email "Re: [Bug c++/60249] [c++11] Compiler 
goes into semi-infinite loop with wrong usage of user defined string 
literals"
A new patch with tweaked testcase is attached.  Sorry for the noise.

I finally fixed these weird user-defined string literal bugs.

I was messing with cp_token stream unnecessarily and poorly.  Changed by 
using a tree in cp_parser_userdef_string_literal.

PR C++/58781  <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58781>  - 
Unicode strings broken in a strange way
PR C++/59867  <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59867>  - 
Template string literal loses first symbol
PR C++/60249  <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60249>  - 
Compiler goes into semi-infinite loop with wrong usage of user defined 
string literals
Plus I fixed an misleading error message for string literal operator 
templates (not available in C++11).

Built and tested clean on x86_64-linux.

OK?

I would also like to apply this to 4.9.

Ed Smith-Rowland


-------------- next part --------------
cp/

2014-06-28  Edward Smith-Rowland  <3dw4rd@verizon.net>

	PR c++/58781
	PR c++/60249
	PR c++/59867
	* parser.c (cp_parser_userdef_string_literal()): Take a tree
	not a cp_token*. (cp_parser_string_literal(): Don't hack
	the token stream!


testsuite/

2014-06-28  Edward Smith-Rowland  <3dw4rd@verizon.net>

	PR c++/58781
	PR c++/60249
	PR c++/59867
	* testsuite/g++.dg/cpp0x/pr58781.C: New.
	* testsuite/g++.dg/cpp0x/pr60249.C: New.
	* testsuite/g++.dg/cpp1y/pr59867.C: New.


-------------- next part --------------
Index: cp/parser.c
===================================================================
--- cp/parser.c	(revision 212100)
+++ cp/parser.c	(working copy)
@@ -1899,7 +1899,7 @@
 static tree cp_parser_userdef_char_literal
   (cp_parser *);
 static tree cp_parser_userdef_string_literal
-  (cp_token *);
+  (tree);
 static tree cp_parser_userdef_numeric_literal
   (cp_parser *);
 
@@ -3721,8 +3721,7 @@
 	{
 	  tree literal = build_userdef_literal (suffix_id, value,
 						OT_NONE, NULL_TREE);
-	  tok->u.value = literal;
-	  return cp_parser_userdef_string_literal (tok);
+	  value = cp_parser_userdef_string_literal (literal);
 	}
     }
   else
@@ -3970,9 +3969,8 @@
    as arguments.  */
 
 static tree
-cp_parser_userdef_string_literal (cp_token *token)
+cp_parser_userdef_string_literal (tree literal)
 {
-  tree literal = token->u.value;
   tree suffix_id = USERDEF_LITERAL_SUFFIX_ID (literal);
   tree name = cp_literal_operator_id (IDENTIFIER_POINTER (suffix_id));
   tree value = USERDEF_LITERAL_VALUE (literal);
@@ -23202,10 +23200,17 @@
 	    ok = false;
 	}
       if (!ok)
-	error ("literal operator template %qD has invalid parameter list."
-	       "  Expected non-type template argument pack <char...>"
-	       " or <typename CharT, CharT...>",
-	       decl);
+	{
+	  if (cxx_dialect >= cxx1y)
+	    error ("literal operator template %qD has invalid parameter list."
+		   "  Expected non-type template argument pack <char...>"
+		   " or <typename CharT, CharT...>",
+		   decl);
+	  else
+	    error ("literal operator template %qD has invalid parameter list."
+		   "  Expected non-type template argument pack <char...>",
+		   decl);
+	}
     }
   /* Register member declarations.  */
   if (member_p && !friend_p && decl && !DECL_CLASS_TEMPLATE_P (decl))
Index: testsuite/g++.dg/cpp0x/pr58781.C
===================================================================
--- testsuite/g++.dg/cpp0x/pr58781.C	(revision 0)
+++ testsuite/g++.dg/cpp0x/pr58781.C	(working copy)
@@ -0,0 +1,18 @@
+// PR c++/58781
+// { dg-do compile { target c++11 } }
+
+#include <cstddef>
+
+int
+operator""_s(const char32_t *a, size_t b)
+{
+  return 0;
+}
+
+int
+f()
+{
+  using a = decltype(U"\x1181"_s);
+  using b = decltype(U"\x8111"_s);
+  using c = decltype(U" \x1181"_s);
+}
Index: testsuite/g++.dg/cpp0x/pr60249.C
===================================================================
--- testsuite/g++.dg/cpp0x/pr60249.C	(revision 0)
+++ testsuite/g++.dg/cpp0x/pr60249.C	(working copy)
@@ -0,0 +1,6 @@
+// PR c++/60249
+// { dg-do compile { target c++11 } }
+
+decltype(""_) x; // { dg-error "unable to find string literal operator" }
+
+// { dg-error "invalid type in declaration before" "invalid" { target *-*-* } 4 }
Index: testsuite/g++.dg/cpp1y/pr59867.C
===================================================================
--- testsuite/g++.dg/cpp1y/pr59867.C	(revision 0)
+++ testsuite/g++.dg/cpp1y/pr59867.C	(working copy)
@@ -0,0 +1,52 @@
+// PR c++/59867
+// { dg-do compile { target c++14 } }
+
+#include <iostream>
+using namespace std;
+
+// constant
+template<typename T, T x>
+  struct meta_value
+  {
+    typedef meta_value type;
+    typedef T value_type;
+    static const T value = x;
+  };
+
+// array
+template<typename T, T... data>
+  struct meta_array
+  {
+    typedef meta_array type;
+    typedef T item_type;
+  };
+
+// static array -> runtime array conversion utility
+template<typename T>
+  struct array_gen;
+
+template<typename T, T... xs>
+  struct array_gen<meta_array<T, xs...>>
+  {
+    static const T value[sizeof...(xs)];
+  };
+
+template<typename T, T... xs>
+  const T
+  array_gen<meta_array<T, xs...>>::value[sizeof...(xs)] = {xs...};
+
+// static string
+template<typename T, T... xs>
+  constexpr meta_array<T, xs...>
+  operator""_s()
+  {
+    static_assert(sizeof...(xs) == 3, "What's wrong with you?");
+    return meta_array<T, xs...>();
+  }
+
+int
+main()
+{
+  auto a = "123"_s;
+  const char (& xs)[3] = array_gen<decltype("123"_s)>::value;
+}