Unbreak the build on Cygwin

* configure.ac (system_malloc) [CYGWIN]: Unset.

diff --git a/configure.ac b/configure.ac
index 7450e2f7274afe2ee6f4c0473f308c450e2fb6ad..d9f52e5b8adfcc2982ca133031a251d22aeaa3a8 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -2157,7 +2157,8 @@ system_malloc=yes
 case "$opsys" in
   ## darwin ld insists on the use of malloc routines in the System framework.
   darwin | mingw32 | nacl | sol2-10) ;;
-  cygwin) hybrid_malloc=yes;;
+  cygwin) hybrid_malloc=yes
+          system_malloc= ;;
   *) test "$ac_cv_func_sbrk" = yes && system_malloc=$emacs_cv_sanitize_address;;
 esac