Description: <short summary of the patch>
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 with a longer explanation of this change. Complete the meta-information
 with other relevant fields (see below for details). To make it easier, the
 information below has been extracted from the changelog. Adjust it or drop
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 .
 gcl (2.6.12-97) unstable; urgency=medium
 .
   * Bug fix: "Removal of obsolete debhelper compat 5 and 6 in bookworm",
     thanks to Niels Thykier (Closes: #965543).
   * Version_2.6.13pre93
Author: Camm Maguire <camm@debian.org>
Bug-Debian: https://bugs.debian.org/965543

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Last-Update: 2020-09-29

--- gcl-2.6.12.orig/o/regexpr.c
+++ gcl-2.6.12/o/regexpr.c
@@ -157,7 +157,7 @@ be over written.   \
 
 
      str=string->st.st_self;
-     if (str+end==(void *)core_end || str+end==(void *)compiled_regexp) {
+     if (NULL_OR_ON_C_STACK(str+end) || str+end==(void *)compiled_regexp) {
 
        if (!(str=alloca(string->st.st_fillp+1)))
 	 FEerror("Cannot allocate memory on C stack",0);