rtl: Forward declare rtx_code

Now that we require C++ 11, we can safely forward declare rtx_code
so that we can use it in target hooks.

gcc/ChangeLog
	* coretypes.h (rtx_code): Add forward declaration.
	* rtl.h (rtx_code): Make compatible with forward declaration.

2 files changed, 5 insertions, 1 deletions

diff --git a/gcc/coretypes.h b/gcc/coretypes.h
index 3e9a2f1..f86dc16 100644
--- a/gcc/coretypes.h
+++ b/gcc/coretypes.h
@@ -101,6 +101,10 @@ typedef gimple *gimple_seq;
 struct gimple_stmt_iterator;
 class code_helper;
 
+/* Forward declare rtx_code, so that we can use it in target hooks without
+   needing to pull in rtl.h.  */
+enum rtx_code : unsigned;
+
 /* Forward decls for leaf gimple subclasses (for individual gimple codes).
    Keep this in the same order as the corresponding codes in gimple.def.  */
 
diff --git a/gcc/rtl.h b/gcc/rtl.h
index e1c5115..0e9491b 100644
--- a/gcc/rtl.h
+++ b/gcc/rtl.h
@@ -45,7 +45,7 @@ class predefined_function_abi;
 /* Register Transfer Language EXPRESSIONS CODES */
 
 #define RTX_CODE	enum rtx_code
-enum rtx_code  {
+enum rtx_code : unsigned {
 
 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS)   ENUM ,
 #include "rtl.def"		/* rtl expressions are documented here */