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, 8 insertions, 6 deletions

diff --git a/gdb/guile/scm-exception.c b/gdb/guile/scm-exception.c
index 73dfb84..ae591cb 100644
--- a/gdb/guile/scm-exception.c
+++ b/gdb/guile/scm-exception.c
@@ -635,22 +635,22 @@ gdbscm_percent_exception_count (void)
 
 static const scheme_function exception_functions[] =
 {
-  { "make-exception", 2, 0, 0, gdbscm_make_exception,
+  { "make-exception", 2, 0, 0, as_a_scm_t_subr (gdbscm_make_exception),
     "\
 Create a <gdb:exception> object.\n\
 \n\
   Arguments: key args\n\
     These are the standard key,args arguments of \"throw\"." },
 
-  { "exception?", 1, 0, 0, gdbscm_exception_p,
+  { "exception?", 1, 0, 0, as_a_scm_t_subr (gdbscm_exception_p),
     "\
 Return #t if the object is a <gdb:exception> object." },
 
-  { "exception-key", 1, 0, 0, gdbscm_exception_key,
+  { "exception-key", 1, 0, 0, as_a_scm_t_subr (gdbscm_exception_key),
     "\
 Return the exception's key." },
 
-  { "exception-args", 1, 0, 0, gdbscm_exception_args,
+  { "exception-args", 1, 0, 0, as_a_scm_t_subr (gdbscm_exception_args),
     "\
 Return the exception's arg list." },
 
@@ -659,11 +659,13 @@ Return the exception's arg list." },
 
 static const scheme_function private_exception_functions[] =
 {
-  { "%exception-print-style", 0, 0, 0, gdbscm_percent_exception_print_style,
+  { "%exception-print-style", 0, 0, 0,
+    as_a_scm_t_subr (gdbscm_percent_exception_print_style),
     "\
 Return the value of the \"guile print-stack\" option." },
 
-  { "%exception-count", 0, 0, 0, gdbscm_percent_exception_count,
+  { "%exception-count", 0, 0, 0,
+    as_a_scm_t_subr (gdbscm_percent_exception_count),
     "\
 Return a count of the number of <gdb:exception> objects created.\n\
 This is for debugging purposes." },