Merge remote-tracking branch 'local-2.0/stable-2.0'

[bpt/guile.git] / libguile / frames.c

diff --git a/libguile/frames.c b/libguile/frames.c
index c7505b2..b90b5a2 100644 (file)
--- a/libguile/frames.c
+++ b/libguile/frames.c
@@ -52,12 +52,12 @@ scm_c_make_frame (SCM stack_holder, SCM *fp, SCM *sp,
 void
 scm_i_frame_print (SCM frame, SCM port, scm_print_state *pstate)
 {
-  scm_puts ("#<frame ", port);
+  scm_puts_unlocked ("#<frame ", port);
   scm_uintprint (SCM_UNPACK (frame), 16, port);
-  scm_putc (' ', port);
+  scm_putc_unlocked (' ', port);
   scm_write (scm_frame_procedure (frame), port);
   /* don't write args, they can get us into trouble. */
-  scm_puts (">", port);
+  scm_puts_unlocked (">", port);
 }
 
 \f
@@ -237,11 +237,16 @@ SCM_DEFINE (scm_frame_instruction_pointer, "frame-instruction-pointer", 1, 0, 0,
            "")
 #define FUNC_NAME s_scm_frame_instruction_pointer
 {
+  SCM program;
   const struct scm_objcode *c_objcode;
 
   SCM_VALIDATE_VM_FRAME (1, frame);
+  program = scm_frame_procedure (frame);
 
-  c_objcode = SCM_PROGRAM_DATA (scm_frame_procedure (frame));
+  if (!SCM_PROGRAM_P (program))
+    return SCM_INUM0;
+
+  c_objcode = SCM_PROGRAM_DATA (program);
   return scm_from_unsigned_integer ((SCM_VM_FRAME_IP (frame)
                                      - SCM_C_OBJCODE_BASE (c_objcode)));
 }