More refactoring for ovector addressing.

src/pcre2_intmodedep.h

@@ -637,7 +637,11 @@ typedef struct pcre2_real_code {
   uint16_t name_count;            /* Number of name entries in the table */
 } pcre2_real_code;
 
-/* The real match data structure. */
+/* The real match data structure. Define ovector large so that array bound 
+checkers don't grumble. Memory for this structure is obtained by calling 
+pcre2_match_data_create(), which sets the size as the offset of ovector plus 
+pairs of elements for each capturing group. (See also the heapframe structure
+below.) */
 
 typedef struct pcre2_real_match_data {
   pcre2_memctl     memctl;
@@ -650,7 +654,7 @@ typedef struct pcre2_real_match_data {
   uint16_t         matchedby;     /* Type of match (normal, JIT, DFA) */
   uint16_t         oveccount;     /* Number of pairs */
   int              rc;            /* The return code from the match */
-  PCRE2_SIZE       ovector[1];    /* The first field */
+  PCRE2_SIZE       ovector[10000];/* The first field */
 } pcre2_real_match_data;
 
 

src/pcre2_match.c

@@ -182,14 +182,8 @@ of use and undefined afterwards. */
 #define Foffset_top        F->offset_top
 #define Foccu              F->occu
 #define Fop                F->op
-#define Freturn_id         F->return_id
-
-/* We need a cast for this one because F->ovector is a vector of size 2, at the 
-end of the backtrack frame, but when there are capturing parentheses the space 
-allocated is bigger so we want to be able to address more elements. Without the 
-case, -fsanitize=undefined grumbles at this. */
-
 #define Fovector           F->ovector
+#define Freturn_id         F->return_id
 
 
 #ifdef DEBUG_FRAMES_DISPLAY

src/pcre2_match_data.c

@@ -59,7 +59,7 @@ pcre2_match_data_create(uint32_t oveccount, pcre2_general_context *gcontext)
 pcre2_match_data *yield;
 if (oveccount < 1) oveccount = 1;
 yield = PRIV(memctl_malloc)(
-  sizeof(pcre2_match_data) + 2*oveccount*sizeof(PCRE2_SIZE),
+  offsetof(pcre2_match_data, ovector) + 2*oveccount*sizeof(PCRE2_SIZE),
   (pcre2_memctl *)gcontext);
 if (yield == NULL) return NULL;
 yield->oveccount = oveccount;