[PATCH] Cast function pointer to expected type

[PATCH] Cast function pointer to expected type

[Andreas Schwab]

The cast is needed to select the correct function call ABI.

Andreas.

2012-03-16  Andreas Schwab  <schwab@linux-m68k.org>

	* linux-fork.c (inferior_call_waitpid): Cast function pointer to
	expected type.
	(checkpoint_command): Likewise.

diff --git a/gdb/linux-fork.c b/gdb/linux-fork.c
index 028fcbc..ddbfa26 100644
--- a/gdb/linux-fork.c
+++ b/gdb/linux-fork.c
@@ -29,6 +29,8 @@
 #include "linux-fork.h"
 #include "linux-nat.h"
 #include "gdbthread.h"
+#include "ui-out.h"
+#include "valprint.h"
 
 #include <sys/ptrace.h>
 #include "gdb_wait.h"
@@ -431,6 +433,7 @@ inferior_call_waitpid (ptid_t pptid, int pid)
   struct objfile *waitpid_objf;
   struct value *waitpid_fn = NULL;
   struct value *argv[4], *retv;
+  struct type *type;
   struct gdbarch *gdbarch = get_current_arch ();
   struct fork_info *oldfp = NULL, *newfp = NULL;
   struct cleanup *old_cleanup;
@@ -459,6 +462,11 @@ inferior_call_waitpid (ptid_t pptid, int pid)
   if (!waitpid_fn)
     goto out;
 
+  /* Cast function pointer to expected type.  */
+  type = lookup_function_type (builtin_type (gdbarch)->builtin_int);
+  type = lookup_pointer_type (type);
+  waitpid_fn = value_cast (type, waitpid_fn);
+
   /* Get the argv.  */
   argv[0] = value_from_longest (builtin_type (gdbarch)->builtin_int, pid);
   argv[1] = value_from_pointer (builtin_type (gdbarch)->builtin_data_ptr, 0);
@@ -650,6 +658,7 @@ checkpoint_command (char *args, int from_tty)
   struct target_waitstatus last_target_waitstatus;
   ptid_t last_target_ptid;
   struct value *fork_fn = NULL, *ret;
+  struct type *type;
   struct fork_info *fp;
   pid_t retpid;
   struct cleanup *old_chain;
@@ -673,13 +682,17 @@ checkpoint_command (char *args, int from_tty)
     error (_("checkpoint: can't find fork function in inferior."));
 
   gdbarch = get_objfile_arch (fork_objf);
-  ret = value_from_longest (builtin_type (gdbarch)->builtin_int, 0);
 
   /* Tell linux-nat.c that we're checkpointing this inferior.  */
   old_chain = make_cleanup_restore_integer (&checkpointing_pid);
   checkpointing_pid = PIDGET (inferior_ptid);
 
-  ret = call_function_by_hand (fork_fn, 0, &ret);
+  /* Cast function pointer to expected type.  */
+  type = lookup_function_type (builtin_type (gdbarch)->builtin_int);
+  type = lookup_pointer_type (type);
+  fork_fn = value_cast (type, fork_fn);
+
+  ret = call_function_by_hand (fork_fn, 0, NULL);
   do_cleanups (old_chain);
   if (!ret)	/* Probably can't happen.  */
     error (_("checkpoint: call_function_by_hand returned null."));
-- 
1.7.9.4


-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

Re: [PATCH] Cast function pointer to expected type

[Jan Kratochvil]

On Fri, 16 Mar 2012 13:14:52 +0100, Andreas Schwab wrote:
> The cast is needed to select the correct function call ABI.

On which arch?  Which testcases are affected by it?


Thanks,
Jan

Re: [PATCH] Cast function pointer to expected type

[Andreas Schwab]

Jan Kratochvil <jan.kratochvil@redhat.com> writes:

> On Fri, 16 Mar 2012 13:14:52 +0100, Andreas Schwab wrote:
>> The cast is needed to select the correct function call ABI.
>
> On which arch?  

m68k-linux

> Which testcases are affected by it?

checkpoint.exp

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."