add zlib checks to configure (new minisat requires it?)

diff --git a/configure.ac b/configure.ac
index 4c90dfd9cff7ef9cd314f8d7f0e56b97a3cc17d9..21f2a9a8b962a330036ca051a03340caab582eed 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -630,6 +630,8 @@ if test -n "$CXXTEST"; then
 fi
 
 # Checks for libraries.
+AC_CHECK_LIB(z, gzread, , [AC_MSG_ERROR([zlib required, install your distro's zlib-dev package or see www.zlib.net])])
+AC_CHECK_HEADER(zlib.h, , [AC_MSG_ERROR([zlib required, install your distro's zlib-dev package or see www.zlib.net])])
 
 # Check for antlr C++ runtime (defined in config/antlr.m4)
 AC_LIB_ANTLR