Merge from origin/emacs-25

50fa7d6 ;* src/w32heap.c: Fix typo and wording of the comments.
6f1325e electric-quote mode no longer worries about coding
c2a1792 * src/regex.c (re_search_2): Make new code safe for -Wjump-mi...
f6134bb Port to GCC 6.2.1 + --enable-gcc-warnings
b2ba630 Explain how to debug emacsclient lisp errors
9da53e2 Let describe-function work for lambda again
5c2da93 Fix kill-line's docstring
ad66b3f Fix handling of allocation in regex matching
5a26c9b * lisp/electric.el (electric-quote-mode): Improve doc (Bug#24...
3877c91 vc-region-history: Search just on lines intersecting the region
8988327 Fix documentation of 'alist-get'
b6998ea * src/regex.h (re_match_object): Improve commentary.

# Conflicts:
#	etc/NEWS
#	lisp/help-fns.el

1 files changed, 77 insertions, 2 deletions

diff --git a/src/regex.c b/src/regex.c
index 1917a8480ae..8bc830356d0 100644
--- a/src/regex.c
+++ b/src/regex.c
@@ -153,6 +153,8 @@
 
 /* Converts the pointer to the char to BEG-based offset from the start.  */
 # define PTR_TO_OFFSET(d) POS_AS_IN_BUFFER (POINTER_TO_OFFSET (d))
+/* Strings are 0-indexed, buffers are 1-indexed; we pun on the boolean
+   result to get the right base index.  */
 # define POS_AS_IN_BUFFER(p) ((p) + (NILP (re_match_object) || BUFFERP (re_match_object)))
 
 # define RE_MULTIBYTE_P(bufp) ((bufp)->multibyte)
@@ -1363,11 +1365,62 @@ typedef struct
 #define NEXT_FAILURE_HANDLE(h) fail_stack.stack[(h) - 3].integer
 #define TOP_FAILURE_HANDLE() fail_stack.frame
 
+#ifdef emacs
+# define STR_BASE_PTR(obj)			 \
+   (NILP (obj) ? current_buffer->text->beg	 \
+    : STRINGP (obj) ? SDATA (obj)		 \
+    : NULL)
+#else
+# define STR_BASE_PTR(obj) NULL
+#endif
 
 #define ENSURE_FAIL_STACK(space)					\
 while (REMAINING_AVAIL_SLOTS <= space) {				\
+  re_char *orig_base = STR_BASE_PTR (re_match_object);                  \
+  bool might_relocate = orig_base != NULL;				\
+  ptrdiff_t string1_off, end1_off, end_match_1_off;                     \
+  ptrdiff_t string2_off, end2_off, end_match_2_off;                     \
+  ptrdiff_t d_off, dend_off, dfail_off;                                 \
+  if (might_relocate)							\
+    {                                                                   \
+      if (string1)                                                      \
+        {                                                               \
+          string1_off = string1 - orig_base;                            \
+          end1_off = end1 - orig_base;                                  \
+          end_match_1_off = end_match_1 - orig_base;                    \
+        }                                                               \
+      if (string2)                                                      \
+        {                                                               \
+          string2_off = string2 - orig_base;                            \
+          end2_off = end2 - orig_base;                                  \
+          end_match_2_off = end_match_2 - orig_base;                    \
+        }                                                               \
+      d_off = d - orig_base;                                            \
+      dend_off = dend - orig_base;                                      \
+      dfail_off = dfail - orig_base;                                    \
+    }                                                                   \
   if (!GROW_FAIL_STACK (fail_stack))					\
     return -2;								\
+  /* In Emacs, GROW_FAIL_STACK might relocate string pointers.  */	\
+  if (might_relocate)							\
+    {                                                                   \
+      re_char *new_base = STR_BASE_PTR (re_match_object);		\
+      if (string1)                                                      \
+        {                                                               \
+          string1 = new_base + string1_off;                             \
+          end1 = new_base + end1_off;                                   \
+          end_match_1 = new_base + end_match_1_off;                     \
+        }                                                               \
+      if (string2)                                                      \
+        {                                                               \
+          string2 = new_base + string2_off;                             \
+          end2 = new_base + end2_off;                                   \
+          end_match_2 = new_base + end_match_2_off;                     \
+        }                                                               \
+      d = new_base + d_off;                                             \
+      dend = new_base + dend_off;                                       \
+      dfail = new_base + dfail_off;                                     \
+    }                                                                   \
   DEBUG_PRINT ("\n  Doubled stack; size now: %zd\n", (fail_stack).size);\
   DEBUG_PRINT ("	 slots available: %zd\n", REMAINING_AVAIL_SLOTS);\
 }
@@ -4293,6 +4346,10 @@ re_search_2 (struct re_pattern_buffer *bufp, const char *str1, size_t size1,
   /* Loop through the string, looking for a place to start matching.  */
   for (;;)
     {
+      ptrdiff_t offset1, offset2;
+      re_char *orig_base;
+      bool might_relocate;
+
       /* If the pattern is anchored,
 	 skip quickly past places we cannot match.
 	 We don't bother to treat startpos == 0 specially
@@ -4409,6 +4466,17 @@ re_search_2 (struct re_pattern_buffer *bufp, const char *str1, size_t size1,
 	  && !bufp->can_be_null)
 	return -1;
 
+      /* re_match_2_internal may allocate, relocating the Lisp text
+	 object that we're searching.  */
+      IF_LINT (offset2 = 0);  /* Work around GCC bug 78081.  */
+      orig_base = STR_BASE_PTR (re_match_object);
+      might_relocate = orig_base != NULL;
+      if (might_relocate)
+        {
+          if (string1) offset1 = string1 - orig_base;
+          if (string2) offset2 = string2 - orig_base;
+        }
+
       val = re_match_2_internal (bufp, string1, size1, string2, size2,
 				 startpos, regs, stop);
 
@@ -4418,6 +4486,13 @@ re_search_2 (struct re_pattern_buffer *bufp, const char *str1, size_t size1,
       if (val == -2)
 	return -2;
 
+      if (might_relocate)
+        {
+	  re_char *new_base = STR_BASE_PTR (re_match_object);
+          if (string1) string1 = offset1 + new_base;
+          if (string2) string2 = offset2 + new_base;
+        }
+
     advance:
       if (!range)
 	break;
@@ -4905,8 +4980,8 @@ WEAK_ALIAS (__re_match, re_match)
 #endif /* not emacs */
 
 #ifdef emacs
-/* In Emacs, this is the string or buffer in which we
-   are matching.  It is used for looking up syntax properties.  */
+/* In Emacs, this is the string or buffer in which we are matching.
+   See the declaration in regex.h for details.  */
 Lisp_Object re_match_object;
 #endif