[pushed] c++: unsigned int32_t enum promotion [PR102804]

[pushed] c++: unsigned int32_t enum promotion [PR102804]

[Jason Merrill]

There's been an extension for a long time to allow applying 'unsigned' to an
int typedef, but that was confusing the integer promotion code.  Fixed by
forgetting about the typedef in that case.

I'm going to make this an unconditional pedwarn in stage 1.

Tested x86_64-pc-linux-gnu, applying to trunk.

	PR c++/102804

gcc/cp/ChangeLog:

	* decl.cc (grokdeclarator): Drop typedef used with 'unsigned'.

gcc/testsuite/ChangeLog:

	* g++.dg/ext/unsigned-typedef1.C: New test.
---
 gcc/cp/decl.cc                               | 2 ++
 gcc/testsuite/g++.dg/ext/unsigned-typedef1.C | 9 +++++++++
 2 files changed, 11 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/ext/unsigned-typedef1.C

diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
index d51fd75b003..2852093d624 100644
--- a/gcc/cp/decl.cc
+++ b/gcc/cp/decl.cc
@@ -12243,6 +12243,8 @@ grokdeclarator (const cp_declarator *declarator,
 	      pedwarn (loc, OPT_Wpedantic, "%qs specified with %qT",
 		       key, type);
 	      ok = !flag_pedantic_errors;
+	      type = DECL_ORIGINAL_TYPE (typedef_decl);
+	      typedef_decl = NULL_TREE;
 	    }
 	  else if (declspecs->decltype_p)
 	    error_at (loc, "%qs specified with %<decltype%>", key);
diff --git a/gcc/testsuite/g++.dg/ext/unsigned-typedef1.C b/gcc/testsuite/g++.dg/ext/unsigned-typedef1.C
new file mode 100644
index 00000000000..360b5f81edf
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/unsigned-typedef1.C
@@ -0,0 +1,9 @@
+// PR c++/102804
+// { dg-do compile { target c++11 } }
+// { dg-options "-Wpedantic" }
+
+using int32_t = int;
+enum: unsigned int32_t { foo };	// { dg-warning "int32_t" }
+int f(int) = delete;
+int f(unsigned);
+auto x = f(1 ? foo : 1);

base-commit: 6364a39907bd68624a30df0c8e380c40d2a646c4
-- 
2.27.0