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, 21 insertions, 18 deletions

diff --git a/gdb/guile/scm-frame.c b/gdb/guile/scm-frame.c
index de77c21..38e1448 100644
--- a/gdb/guile/scm-frame.c
+++ b/gdb/guile/scm-frame.c
@@ -1075,86 +1075,89 @@ static const scheme_integer_constant frame_integer_constants[] =
 
 static const scheme_function frame_functions[] =
 {
-  { "frame?", 1, 0, 0, gdbscm_frame_p,
+  { "frame?", 1, 0, 0, as_a_scm_t_subr (gdbscm_frame_p),
     "\
 Return #t if the object is a <gdb:frame> object." },
 
-  { "frame-valid?", 1, 0, 0, gdbscm_frame_valid_p,
+  { "frame-valid?", 1, 0, 0, as_a_scm_t_subr (gdbscm_frame_valid_p),
     "\
 Return #t if the object is a valid <gdb:frame> object.\n\
 Frames become invalid when the inferior returns to its caller." },
 
-  { "frame-name", 1, 0, 0, gdbscm_frame_name,
+  { "frame-name", 1, 0, 0, as_a_scm_t_subr (gdbscm_frame_name),
     "\
 Return the name of the function corresponding to this frame,\n\
 or #f if there is no function." },
 
-  { "frame-arch", 1, 0, 0, gdbscm_frame_arch,
+  { "frame-arch", 1, 0, 0, as_a_scm_t_subr (gdbscm_frame_arch),
     "\
 Return the frame's architecture as a <gdb:arch> object." },
 
-  { "frame-type", 1, 0, 0, gdbscm_frame_type,
+  { "frame-type", 1, 0, 0, as_a_scm_t_subr (gdbscm_frame_type),
     "\
 Return the frame type, namely one of the gdb:*_FRAME constants." },
 
-  { "frame-unwind-stop-reason", 1, 0, 0, gdbscm_frame_unwind_stop_reason,
+  { "frame-unwind-stop-reason", 1, 0, 0,
+    as_a_scm_t_subr (gdbscm_frame_unwind_stop_reason),
     "\
 Return one of the gdb:FRAME_UNWIND_* constants explaining why\n\
 it's not possible to find frames older than this." },
 
-  { "frame-pc", 1, 0, 0, gdbscm_frame_pc,
+  { "frame-pc", 1, 0, 0, as_a_scm_t_subr (gdbscm_frame_pc),
     "\
 Return the frame's resume address." },
 
-  { "frame-block", 1, 0, 0, gdbscm_frame_block,
+  { "frame-block", 1, 0, 0, as_a_scm_t_subr (gdbscm_frame_block),
     "\
 Return the frame's code block, or #f if one cannot be found." },
 
-  { "frame-function", 1, 0, 0, gdbscm_frame_function,
+  { "frame-function", 1, 0, 0, as_a_scm_t_subr (gdbscm_frame_function),
     "\
 Return the <gdb:symbol> for the function corresponding to this frame,\n\
 or #f if there isn't one." },
 
-  { "frame-older", 1, 0, 0, gdbscm_frame_older,
+  { "frame-older", 1, 0, 0, as_a_scm_t_subr (gdbscm_frame_older),
     "\
 Return the frame immediately older (outer) to this frame,\n\
 or #f if there isn't one." },
 
-  { "frame-newer", 1, 0, 0, gdbscm_frame_newer,
+  { "frame-newer", 1, 0, 0, as_a_scm_t_subr (gdbscm_frame_newer),
     "\
 Return the frame immediately newer (inner) to this frame,\n\
 or #f if there isn't one." },
 
-  { "frame-sal", 1, 0, 0, gdbscm_frame_sal,
+  { "frame-sal", 1, 0, 0, as_a_scm_t_subr (gdbscm_frame_sal),
     "\
 Return the frame's symtab-and-line <gdb:sal> object." },
 
-  { "frame-read-var", 2, 0, 1, gdbscm_frame_read_var,
+  { "frame-read-var", 2, 0, 1, as_a_scm_t_subr (gdbscm_frame_read_var),
     "\
 Return the value of the symbol in the frame.\n\
 \n\
   Arguments: <gdb:frame> <gdb:symbol>\n\
          Or: <gdb:frame> string [#:block <gdb:block>]" },
 
-  { "frame-read-register", 2, 0, 0, gdbscm_frame_read_register,
+  { "frame-read-register", 2, 0, 0,
+    as_a_scm_t_subr (gdbscm_frame_read_register),
     "\
 Return the value of the register in the frame.\n\
 \n\
   Arguments: <gdb:frame> string" },
 
-  { "frame-select", 1, 0, 0, gdbscm_frame_select,
+  { "frame-select", 1, 0, 0, as_a_scm_t_subr (gdbscm_frame_select),
     "\
 Select this frame." },
 
-  { "newest-frame", 0, 0, 0, gdbscm_newest_frame,
+  { "newest-frame", 0, 0, 0, as_a_scm_t_subr (gdbscm_newest_frame),
     "\
 Return the newest frame." },
 
-  { "selected-frame", 0, 0, 0, gdbscm_selected_frame,
+  { "selected-frame", 0, 0, 0, as_a_scm_t_subr (gdbscm_selected_frame),
     "\
 Return the selected frame." },
 
-  { "unwind-stop-reason-string", 1, 0, 0, gdbscm_unwind_stop_reason_string,
+  { "unwind-stop-reason-string", 1, 0, 0,
+    as_a_scm_t_subr (gdbscm_unwind_stop_reason_string),
     "\
 Return a string explaining the unwind stop reason.\n\
 \n\