Fix zero-repeated subroutine call at start of pattern bug, which recorded an

incorrect first code unit.

ChangeLog

@@ -43,6 +43,11 @@ path. Also, when a match fails, set the subject field in the match data to NULL
 for tidiness - none of the substring extractors should reference this after 
 match failure.
 
+11. If a pattern started with a subroutine call that had a quantifier with a 
+minimum of zero, an incorrect "match must start with this character" could be 
+recorded. Example: /(?&xxx)*ABC(?<xxx>XYZ)/ would (incorrectly) expect 'A' to 
+be the first character of a match. 
+
 
 Version 10.32 10-September-2018
 -------------------------------

src/pcre2_compile.c

@@ -6095,7 +6095,7 @@ for (;; pptr++)
       }
     goto GROUP_PROCESS_NOTE_EMPTY;
 
-    /* The DEFINE condition is always false. It's internal groups may never
+    /* The DEFINE condition is always false. Its internal groups may never
     be called, so matched_char must remain false, hence the jump to
     GROUP_PROCESS rather than GROUP_PROCESS_NOTE_EMPTY. */
 
@@ -6435,8 +6435,8 @@ for (;; pptr++)
           groupnumber = ng->number;
 
           /* For a recursion, that's all that is needed. We can now go to
-          the code above that handles numerical recursion, applying it to
+          the code that handles numerical recursion, applying it to the first
-          the first group with the given name. */
+          group with the given name. */
 
           if (meta == META_RECURSE_BYNAME)
             {
@@ -7486,6 +7486,8 @@ for (;; pptr++)
     groupsetfirstcu = FALSE;
     cb->had_recurse = TRUE;
     if (firstcuflags == REQ_UNSET) firstcuflags = REQ_NONE;
+    zerofirstcu = firstcu;
+    zerofirstcuflags = firstcuflags;   
     break;
 
 

testdata/testinput1

@@ -6328,4 +6328,19 @@ ef) x/x,mark
 \= Expect no match
     aaaa      
 
+/   (?<word> \w+ )*    \.   /xi
+    pokus.
+    
+/(?(DEFINE) (?<word> \w+ ) ) (?&word)*   \./xi
+    pokus.
+
+/(?(DEFINE) (?<word> \w+ ) ) ( (?&word)* )   \./xi 
+    pokus.
+
+/(?&word)*  (?(DEFINE) (?<word> \w+ ) )  \./xi
+    pokus.
+
+/(?&word)*  \. (?<word> \w+ )/xi
+    pokus.hokus
+
 # End of testinput1 

testdata/testoutput1

@@ -10025,4 +10025,28 @@ No match
     aaaa      
 No match
 
+/   (?<word> \w+ )*    \.   /xi
+    pokus.
+ 0: pokus.
+ 1: pokus
+    
+/(?(DEFINE) (?<word> \w+ ) ) (?&word)*   \./xi
+    pokus.
+ 0: pokus.
+
+/(?(DEFINE) (?<word> \w+ ) ) ( (?&word)* )   \./xi 
+    pokus.
+ 0: pokus.
+ 1: <unset>
+ 2: pokus
+
+/(?&word)*  (?(DEFINE) (?<word> \w+ ) )  \./xi
+    pokus.
+ 0: pokus.
+
+/(?&word)*  \. (?<word> \w+ )/xi
+    pokus.hokus
+ 0: pokus.hokus
+ 1: hokus
+
 # End of testinput1