guile: Add as_a_scm_t_subr

Building GDB in C++ mode on Fedora 20, the gdb/guile/ code shows ~280
errors like:

 src/gdb/guile/guile.c:515:1: error: invalid conversion from ‘scm_unused_struct* (*)(SCM, SCM) {aka scm_unused_struct* (*)(scm_unused_struct*, scm_unused_struct*)}’ to ‘scm_t_subr {aka void*}’ [-fpermissive]

This commit fixes them all.

gdb/ChangeLog:
2015-09-07  Pedro Alves  <palves@redhat.com>

	* guile/guile-internal.h (as_a_scm_t_subr): New.
	* guile/guile.c (misc_guile_functions): Use it.
	* guile/scm-arch.c (arch_functions): Use it.
	* guile/scm-block.c (block_functions, gdbscm_initialize_blocks):
	Use it.
	* guile/scm-breakpoint.c (breakpoint_functions): Use it.
	* guile/scm-cmd.c (command_functions): Use it.
	* guile/scm-disasm.c (disasm_functions): Use it.
	* guile/scm-exception.c (exception_functions)
	(private_exception_functions): Use it.
	* guile/scm-frame.c (frame_functions)
	* guile/scm-gsmob.c (gsmob_functions): Use it.
	* guile/scm-iterator.c (iterator_functions): Use it.
	* guile/scm-lazy-string.c (lazy_string_functions): Use it.
	* guile/scm-math.c (math_functions): Use it.
	* guile/scm-objfile.c (objfile_functions): Use it.
	* guile/scm-param.c (parameter_functions): Use it.
	* guile/scm-ports.c (port_functions, private_port_functions): Use
	it.
	* guile/scm-pretty-print.c (pretty_printer_functions): Use it.
	* guile/scm-progspace.c (pspace_functions): Use it.
	* guile/scm-string.c (string_functions): Use it.
	* guile/scm-symbol.c (symbol_functions): Use it.
	* guile/scm-symtab.c (symtab_functions): Use it.
	* guile/scm-type.c (type_functions, gdbscm_initialize_types): Use
	it.
	* guile/scm-value.c (value_functions): Use it.

1 files changed, 12 insertions, 8 deletions

diff --git a/gdb/guile/scm-pretty-print.c b/gdb/guile/scm-pretty-print.c
index 879c4ea..a288a64 100644
--- a/gdb/guile/scm-pretty-print.c
+++ b/gdb/guile/scm-pretty-print.c
@@ -1055,7 +1055,8 @@ gdbscm_apply_val_pretty_printer (const struct extension_language_defn *extlang,
 
 static const scheme_function pretty_printer_functions[] =
 {
-  { "make-pretty-printer", 2, 0, 0, gdbscm_make_pretty_printer,
+  { "make-pretty-printer", 2, 0, 0,
+    as_a_scm_t_subr (gdbscm_make_pretty_printer),
     "\
 Create a <gdb:pretty-printer> object.\n\
 \n\
@@ -1064,21 +1065,23 @@ Create a <gdb:pretty-printer> object.\n\
     lookup: a procedure:\n\
       (pretty-printer <gdb:value>) -> <gdb:pretty-printer-worker> | #f." },
 
-  { "pretty-printer?", 1, 0, 0, gdbscm_pretty_printer_p,
+  { "pretty-printer?", 1, 0, 0, as_a_scm_t_subr (gdbscm_pretty_printer_p),
     "\
 Return #t if the object is a <gdb:pretty-printer> object." },
 
-  { "pretty-printer-enabled?", 1, 0, 0, gdbscm_pretty_printer_enabled_p,
+  { "pretty-printer-enabled?", 1, 0, 0,
+    as_a_scm_t_subr (gdbscm_pretty_printer_enabled_p),
     "\
 Return #t if the pretty-printer is enabled." },
 
   { "set-pretty-printer-enabled!", 2, 0, 0,
-    gdbscm_set_pretty_printer_enabled_x,
+    as_a_scm_t_subr (gdbscm_set_pretty_printer_enabled_x),
     "\
 Set the enabled flag of the pretty-printer.\n\
 Returns \"unspecified\"." },
 
-  { "make-pretty-printer-worker", 3, 0, 0, gdbscm_make_pretty_printer_worker,
+  { "make-pretty-printer-worker", 3, 0, 0,
+    as_a_scm_t_subr (gdbscm_make_pretty_printer_worker),
     "\
 Create a <gdb:pretty-printer-worker> object.\n\
 \n\
@@ -1089,16 +1092,17 @@ Create a <gdb:pretty-printer-worker> object.\n\
     children:     either #f or a procedure:\n\
       (pretty-printer) -> <gdb:iterator>" },
 
-  { "pretty-printer-worker?", 1, 0, 0, gdbscm_pretty_printer_worker_p,
+  { "pretty-printer-worker?", 1, 0, 0,
+    as_a_scm_t_subr (gdbscm_pretty_printer_worker_p),
     "\
 Return #t if the object is a <gdb:pretty-printer-worker> object." },
 
-  { "pretty-printers", 0, 0, 0, gdbscm_pretty_printers,
+  { "pretty-printers", 0, 0, 0, as_a_scm_t_subr (gdbscm_pretty_printers),
     "\
 Return the list of global pretty-printers." },
 
   { "set-pretty-printers!", 1, 0, 0,
-    gdbscm_set_pretty_printers_x,
+    as_a_scm_t_subr (gdbscm_set_pretty_printers_x),
     "\
 Set the list of global pretty-printers." },