Hi,
This patch fixes https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82307.
For an unscoped enum with a fixed underlying type, the function
type_promotes_to() does not always return the same type as the
underlying type. The fix is to use the underlying type of the enum
instead of creating a new one by calling c_common_type_for_size().
Bootstrapped and tested with 'make check' on x86_64-linux. New test case
added.
Mukesh
Index: gcc/cp/cvt.c
===================================================================
--- gcc/cp/cvt.c (revision 253551)
+++ gcc/cp/cvt.c (working copy)
@@ -1854,11 +1854,16 @@
tree prom = type;
if (TREE_CODE (prom) == ENUMERAL_TYPE)
prom = ENUM_UNDERLYING_TYPE (prom);
- if (TYPE_UNSIGNED (prom)
- && ! int_fits_type_p (TYPE_MAX_VALUE (prom), totype))
- prom = c_common_type_for_size (precision, 1);
- else
- prom = totype;
+ // If an unscoped enum has fixed underlying type,
+ // use that type (bug 82307)
+ if (!ENUM_FIXED_UNDERLYING_TYPE_P (type) || SCOPED_ENUM_P (type))
+ {
+ if (TYPE_UNSIGNED (prom)
+ && ! int_fits_type_p (TYPE_MAX_VALUE (prom), totype))
+ prom = c_common_type_for_size (precision, 1);
+ else
+ prom = totype;
+ }
if (SCOPED_ENUM_P (type))
{
if (abi_version_crosses (6)
Index: gcc/testsuite/g++.dg/cpp0x/pr_82307.C
===================================================================
--- gcc/testsuite/g++.dg/cpp0x/pr_82307.C (revision 0)
+++ gcc/testsuite/g++.dg/cpp0x/pr_82307.C (working copy)
@@ -0,0 +1,24 @@
+// PR c++/82307
+// { dg-do compile { target c++11 } }
+
+#include <cstdlib>
+#include <cstring>
+
+enum : unsigned long long { VAL };
+
+const char* foo( unsigned long long )
+{
+ return "unsigned long long";
+}
+
+const char* foo( int )
+{
+ return "int";
+}
+
+int main( void )
+{
+ if (strcmp(foo(VAL), "unsigned long long") != 0)
+ abort();
+}
+
