Resolves: #1441092 - compile with -fconserve-stack to prevent stack overflow

zsh.spec

@@ -3,7 +3,7 @@
 Summary: Powerful interactive shell
 Name: zsh
 Version: 5.3.1
-Release: 4%{?dist}
+Release: 5%{?dist}
 License: MIT
 URL: http://zsh.sourceforge.net/
 Group: System Environment/Shells
@@ -68,6 +68,13 @@ This package contains the Zsh manual in html format.
 cp -p %SOURCE7 .
 
 %build
+# Compile with -fconserve-stack to prevent stack overflow while executing
+# unbounded call recursion in a shell script.  Without this compiler flag,
+# the default stack allocation limit (8192 KiB) is exceeded before the default
+# shell call nesting limit (1000) is reached.  See #1441092 for details.
+# Minimal example: zsh -c 'foo() { if true; then foo; fi }; foo'
+export CFLAGS="$RPM_OPT_FLAGS -fconserve-stack"
+
 # make loading of module's dependencies work again (#1277996)
 export LIBLDFLAGS='-z lazy'
 
@@ -171,9 +178,13 @@ fi
 %doc Doc/*.html
 
 %changelog
+* Thu May 11 2017 Kamil Dudka <kdudka@redhat.com> - 5.3.1-5
+- compile with -fconserve-stack to prevent stack overflow (#1441092)
+
 * Fri Mar 31 2017 Jason L Tibbitts III <tibbs@math.uh.edu> - 5.3.1-4
 - Add build deps on gdbm-devel and pcre-devel.  Pass --enable-pcre to
   configure.  These should ensure that the pcre and gdbm modules are built.
+  (#1438009)
 
 * Sat Feb 11 2017 Fedora Release Engineering <releng@fedoraproject.org> - 5.3.1-3
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_26_Mass_Rebuild