compiler: add -fgo-c-header=FILE to create a C header

    
    The new -fgo-c-header=FILE option will write a C header file defining
    all the struct types and numeric const values in package scope.  This
    will be used when building the Go runtime package (libgo/go/runtime) to
    generate a C header file that may be included by the C code in the C
    runtime package (libgo/runtime).
    
    This will ensure that the Go code and C code are working with the same
    data structures as we convert the runtime from C to Go to upgrade to the
    current GC runtime, notably the concurrent garbage collector.
    
    Reviewed-on: https://go-review.googlesource.com/28000

	* lang.opt (fgo-c-header, fgo-compiling-runtime): New options.
	* go-c.h (struct go_create_gogo_args): Define.
	(go_create_gogo): Change declaration to take struct pointer.
	* go-lang.c (go_c_header): New static variable.
	(go_langhook_init): Update call to go_create_gogo.
	* gccgo.texi (Invoking gccgo): Document -fgo-c-header and
	-fgo-compiling-runtime.

From-SVN: r239852

1 files changed, 17 insertions, 3 deletions

diff --git a/gcc/go/go-lang.c b/gcc/go/go-lang.c
index 570f5e0..88667e0 100644
--- a/gcc/go/go-lang.c
+++ b/gcc/go/go-lang.c
@@ -83,6 +83,7 @@ struct GTY(()) language_function
 static const char *go_pkgpath = NULL;
 static const char *go_prefix = NULL;
 static const char *go_relative_import_path = NULL;
+static const char *go_c_header = NULL;
 
 /* Language hooks.  */
 
@@ -99,9 +100,18 @@ go_langhook_init (void)
      to, e.g., unsigned_char_type_node) but before calling
      build_common_builtin_nodes (because it calls, indirectly,
      go_type_for_size).  */
-  go_create_gogo (INT_TYPE_SIZE, POINTER_SIZE, go_pkgpath, go_prefix,
-		  go_relative_import_path, go_check_divide_zero,
-		  go_check_divide_overflow, go_debug_escape_level);
+  struct go_create_gogo_args args;
+  args.int_type_size = INT_TYPE_SIZE;
+  args.pointer_size = POINTER_SIZE;
+  args.pkgpath = go_pkgpath;
+  args.prefix = go_prefix;
+  args.relative_import_path = go_relative_import_path;
+  args.c_header = go_c_header;
+  args.check_divide_by_zero = go_check_divide_zero;
+  args.check_divide_overflow = go_check_divide_overflow;
+  args.compiling_runtime = go_compiling_runtime;
+  args.debug_escape_level = go_debug_escape_level;
+  go_create_gogo (&args);
 
   build_common_builtin_nodes ();
 
@@ -247,6 +257,10 @@ go_langhook_handle_option (
       go_relative_import_path = arg;
       break;
 
+    case OPT_fgo_c_header_:
+      go_c_header = arg;
+      break;
+
     default:
       /* Just return 1 to indicate that the option is valid.  */
       break;