https://sourceforge.net/tracker/?func=detail&aid=3489349&group_id=224196&atid=1060899
--- libqpdf/PCRE.cc.orig
+++ libqpdf/PCRE.cc
@@ -144,7 +144,7 @@
     this->code = pcre_compile(pattern, options, &errptr, &erroffset, 0);
     if (this->code)
     {
-	this->nbackrefs = pcre_info(this->code, 0, 0);
+	pcre_fullinfo(this->code, 0, PCRE_INFO_CAPTURECOUNT, &(this->nbackrefs));
     }
     else
     {
