[gcc r11-7877] d: Define language hook for LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE

[Iain Buclaw <ibuclaw@gcc.gnu.org>]

https://gcc.gnu.org/g:0907036f4541cfb51a626ef13c282f7be2098add

commit r11-7877-g0907036f4541cfb51a626ef13c282f7be2098add
Author: Iain Buclaw <ibuclaw@gdcproject.org>
Date:   Sat Mar 27 02:31:45 2021 +0100

    d: Define language hook for LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE
    
    The underlying base type for enumerals are always present in TREE_TYPE.
    
    gcc/d/ChangeLog:
    
            * d-lang.cc (d_enum_underlying_base_type): New function.
            (LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE): Set as
            d_enum_underlying_base_type.

Diff:
---
 gcc/d/d-lang.cc | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/gcc/d/d-lang.cc b/gcc/d/d-lang.cc
index 0720cba1340..5028698a5bc 100644
--- a/gcc/d/d-lang.cc
+++ b/gcc/d/d-lang.cc
@@ -1719,6 +1719,16 @@ d_build_eh_runtime_type (tree type)
   return convert (ptr_type_node, build_address (decl));
 }
 
+/* Implements the lang_hooks.enum_underlying_base_type routine for language D.
+   Returns the underlying type of the given enumeration TYPE.  */
+
+static tree
+d_enum_underlying_base_type (const_tree type)
+{
+  gcc_assert (TREE_CODE (type) == ENUMERAL_TYPE);
+  return TREE_TYPE (type);
+}
+
 /* Definitions for our language-specific hooks.  */
 
 #undef LANG_HOOKS_NAME
@@ -1744,6 +1754,7 @@ d_build_eh_runtime_type (tree type)
 #undef LANG_HOOKS_DUP_LANG_SPECIFIC_DECL
 #undef LANG_HOOKS_EH_PERSONALITY
 #undef LANG_HOOKS_EH_RUNTIME_TYPE
+#undef LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE
 #undef LANG_HOOKS_PUSHDECL
 #undef LANG_HOOKS_GETDECLS
 #undef LANG_HOOKS_GLOBAL_BINDINGS_P
@@ -1774,6 +1785,7 @@ d_build_eh_runtime_type (tree type)
 #define LANG_HOOKS_DUP_LANG_SPECIFIC_DECL   d_dup_lang_specific_decl
 #define LANG_HOOKS_EH_PERSONALITY	    d_eh_personality
 #define LANG_HOOKS_EH_RUNTIME_TYPE	    d_build_eh_runtime_type
+#define LANG_HOOKS_ENUM_UNDERLYING_BASE_TYPE d_enum_underlying_base_type
 #define LANG_HOOKS_PUSHDECL		    d_pushdecl
 #define LANG_HOOKS_GETDECLS		    d_getdecls
 #define LANG_HOOKS_GLOBAL_BINDINGS_P	    d_global_bindings_p