(skip_chars): If enable-multibyte-characters is nil,

[gnu-emacs] / src / bytecode.c

diff --git a/src/bytecode.c b/src/bytecode.c
index 92406a78c325e89a9e78dfee901097d0cd933b8f..38a1d3a0d5d7ee2070974facbcd81afec683d18d 100644 (file)
--- a/src/bytecode.c
+++ b/src/bytecode.c
@@ -256,7 +256,24 @@ Lisp_Object Qbytecode;
 
 #define MAYBE_GC()                             \
   if (consing_since_gc > gc_cons_threshold)    \
-    Fgarbage_collect ();
+    {                                          \
+      Fgarbage_collect ();                     \
+      HANDLE_RELOCATION ();                    \
+    }                                          \
+  else
+
+/* Relocate BYTESTR if there has been a GC recently.  */
+#define HANDLE_RELOCATION()                                            \
+  if (! EQ (string_saved, bytestr))                                    \
+    {                                                                  \
+      pc = pc - XSTRING (string_saved)->data + XSTRING (bytestr)->data;        \
+      string_saved = bytestr;                                          \
+    }                                                                  \
+  else
+
+/* Check for jumping out of range.  */
+#define CHECK_RANGE(ARG)                       \
+  if (ARG >= bytestr_length) abort ()
 
 DEFUN ("byte-code", Fbyte_code, Sbyte_code, 3, 3, 0,
   "Function used internally in byte-compiled code.\n\
@@ -288,6 +305,7 @@ If the third argument is incorrect, Emacs may crash.")
   /* Cached address of beginning of string,
      valid if BYTESTR equals STRING_SAVED.  */
   register unsigned char *strbeg;
+  int bytestr_length = XSTRING (bytestr)->size;
 
   CHECK_STRING (bytestr, 0);
   if (!VECTORP (vector))
@@ -318,11 +336,8 @@ If the third argument is incorrect, Emacs may crash.")
               pc - XSTRING (string_saved)->data);
 #endif
 
-      if (! EQ (string_saved, bytestr))
-       {
-         pc = pc - XSTRING (string_saved)->data + XSTRING (bytestr)->data;
-         string_saved = bytestr;
-       }
+      /* Update BYTESTR if we had a garbage collection.  */
+      HANDLE_RELOCATION ();
 
 #ifdef BYTE_CODE_METER
       prev_op = this_op;
@@ -441,6 +456,7 @@ If the third argument is incorrect, Emacs may crash.")
          MAYBE_GC ();
          QUIT;
          op = FETCH2;    /* pc = FETCH2 loses since FETCH2 contains pc++ */
+         CHECK_RANGE (op);
          pc = XSTRING (string_saved)->data + op;
          break;
 
@@ -450,6 +466,7 @@ If the third argument is incorrect, Emacs may crash.")
          if (NILP (POP))
            {
              QUIT;
+             CHECK_RANGE (op);
              pc = XSTRING (string_saved)->data + op;
            }
          break;
@@ -460,6 +477,7 @@ If the third argument is incorrect, Emacs may crash.")
          if (!NILP (POP))
            {
              QUIT;
+             CHECK_RANGE (op);
              pc = XSTRING (string_saved)->data + op;
            }
          break;
@@ -470,6 +488,7 @@ If the third argument is incorrect, Emacs may crash.")
          if (NILP (TOP))
            {
              QUIT;
+             CHECK_RANGE (op);
              pc = XSTRING (string_saved)->data + op;
            }
          else DISCARD (1);
@@ -481,6 +500,7 @@ If the third argument is incorrect, Emacs may crash.")
          if (!NILP (TOP))
            {
              QUIT;
+             CHECK_RANGE (op);
              pc = XSTRING (string_saved)->data + op;
            }
          else DISCARD (1);