Fix \g+ bug when the number that follows is too big.

ChangeLog

@@ -330,7 +330,7 @@ AC_USE_SYSTEM_EXTENSIONS macro and to test for functions used by the JIT
 modules.
 
 52. Minor fixed to pcre2grep from Jason Hood:
-    * fixes some spacing;
+    * fixed some spacing;
     * Windows doesn't usually use single quotes, so I've added a define
       to use appropriate quotes [in an example];
     * LC_ALL was displayed as "LCC_ALL";

src/pcre2_compile.c

@@ -1220,9 +1220,20 @@ BOOL yield = FALSE;
 
 *errorcodeptr = 0;
 
-if (allow_sign >= 0 && ptr < ptrend &&
-    (*ptr == CHAR_PLUS || *ptr == CHAR_MINUS))
-  sign = (*ptr++ == CHAR_MINUS)? -1 : +1;
+if (allow_sign >= 0 && ptr < ptrend)
+  {
+  if (*ptr == CHAR_PLUS)
+    {
+    sign = +1;
+    max_value -= allow_sign;
+    ptr++; 
+    }
+  else if (*ptr == CHAR_MINUS)
+    { 
+    sign = -1;        
+    ptr++; 
+    } 
+  } 
 
 if (ptr >= ptrend || !IS_DIGIT(*ptr)) return FALSE;
 while (ptr < ptrend && IS_DIGIT(*ptr))

testdata/testinput2

@@ -4959,4 +4959,8 @@ a)"xI
 /abcd/auto_callout
     abcd\=callout_error=255:2
 
+/()(\g+65534)/
+
+/()(\g+65533)/
+
 # End of testinput2 

testdata/testoutput2

@@ -15446,6 +15446,12 @@ Failed: error 128 at offset 11: assertion expected after (?( or (?(?C)
  +1 ^^       b
 Failed: error -37: callout error code
 
+/()(\g+65534)/
+Failed: error 161 at offset 11: group number is too big
+
+/()(\g+65533)/
+Failed: error 115 at offset 10: reference to non-existent subpattern
+
 # End of testinput2 
 Error -63: PCRE2_ERROR_BADDATA (unknown error number)
 Error -62: bad serialized data