Re: Interoperability with C int128_t type?

[Sa Liu <SALIU at de dot ibm dot com>]

> I was thinking of a more straightforward way: if we compile with - 
> std=gnu (the default), we make C_INT128_T defined, otherwise (when - 
> std=f2003 or -std=f2008 is specified) we simply do not define it (and 
> the user will have the current message, which is probably something 
> like "C_INT128_T is not defined").

Is this patch OK for this extension?

Index: gcc/gcc/fortran/iso-c-binding.def
===================================================================
--- gcc.orig/gcc/fortran/iso-c-binding.def
+++ gcc/gcc/fortran/iso-c-binding.def
@@ -65,6 +65,8 @@ NAMED_INTCST (ISOCBINDING_INT8_T, "c_int
 NAMED_INTCST (ISOCBINDING_INT16_T, "c_int16_t", get_int_kind_from_width 
(16))
 NAMED_INTCST (ISOCBINDING_INT32_T, "c_int32_t", get_int_kind_from_width 
(32))
 NAMED_INTCST (ISOCBINDING_INT64_T, "c_int64_t", get_int_kind_from_width 
(64))
+/* GNU Extension.  */
+NAMED_INTCST (ISOCBINDING_INT128_T, "c_int128_t", get_int_kind_from_width 
(128))
 
 NAMED_INTCST (ISOCBINDING_INT_LEAST8_T, "c_int_least8_t", \
               get_int_kind_from_minimal_width (8))
@@ -74,12 +76,17 @@ NAMED_INTCST (ISOCBINDING_INT_LEAST32_T,
               get_int_kind_from_minimal_width (32))
 NAMED_INTCST (ISOCBINDING_INT_LEAST64_T, "c_int_least64_t", \
               get_int_kind_from_minimal_width (64))
+/* GNU Extension.  */
+NAMED_INTCST (ISOCBINDING_INT_LEAST128_T, "c_int_least128_t", \
+              get_int_kind_from_minimal_width (128))
 
 /* TODO: Implement c_int_fast*_t. Depends on PR 448.  */ 
 NAMED_INTCST (ISOCBINDING_INT_FAST8_T, "c_int_fast8_t", -2)
 NAMED_INTCST (ISOCBINDING_INT_FAST16_T, "c_int_fast16_t", -2)
 NAMED_INTCST (ISOCBINDING_INT_FAST32_T, "c_int_fast32_t", -2)
 NAMED_INTCST (ISOCBINDING_INT_FAST64_T, "c_int_fast64_t", -2)
+/* GNU Extension.  */
+NAMED_INTCST (ISOCBINDING_INT_FAST128_T, "c_int_fast128_t", -2)
 
 NAMED_REALCST (ISOCBINDING_FLOAT, "c_float", \
                get_real_kind_from_node (float_type_node))
Index: gcc/gcc/fortran/symbol.c
===================================================================
--- gcc.orig/gcc/fortran/symbol.c
+++ gcc/gcc/fortran/symbol.c
@@ -3836,6 +3836,12 @@ generate_isocbinding_symbol (const char 
 #define NAMED_CHARKNDCST(a,b,c) case a :
 #include "iso-c-binding.def"
 
+       /* c_int128_t, c_int_least128_t and c_int_fast128_t are gnu 
extensions.  */
+       if (gfc_notification_std (GFC_STD_GNU) == FAILURE
+           && (s == ISOCBINDING_INT128_T || s == 
ISOCBINDING_INT_LEAST128_T
+               || s == ISOCBINDING_INT_FAST128_T))
+         break;
+
        tmp_sym->value = gfc_int_expr (c_interop_kinds_table[s].value);
 
        /* Initialize an integer constant expression node.  */

Thanks!
Sa