From c2f9b78afe15bfb9e0fa89bbb93e7b4aafd9d7b4 Mon Sep 17 00:00:00 2001
From: Dambaev Alexander <theice@inbox.ru>
Date: Thu, 11 Aug 2016 23:49:48 +0800
Subject: [PATCH] configure.ac: add zlib search with pkg-config

Closes #956
---
 configure.ac | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/configure.ac b/configure.ac
index 3c2fe2705..e1dbbee84 100644
--- a/configure.ac
+++ b/configure.ac
@@ -892,16 +892,26 @@ else
   fi
 
   if test -z "$OPT_ZLIB" ; then
-    dnl check for the lib first without setting any new path, since many
-    dnl people have it in the default path
+    PKG_CHECK_MODULES(ZLIB, zlib,
+        [ LIBS="${ZLIB_LIBS} $LIBS"
+          CPPFLAGS="${ZLIB_CFLAGS} $CPPFLAGS"
+          HAVE_LIBZ="1"
+        ],
+        [
+        ])
 
-    AC_CHECK_LIB(z, inflateEnd,
+    if test -z "$HAVE_LIBZ"; then
+
+      dnl Check for the lib without setting any new path, since many
+      dnl people have it in the default path
+
+      AC_CHECK_LIB(z, inflateEnd,
                    dnl libz found, set the variable
                    [HAVE_LIBZ="1"
                     LIBS="-lz $LIBS"],
                    dnl if no lib found, try /usr/local
                    [OPT_ZLIB="/usr/local"])
-
+    fi
   fi
 
   dnl Add a nonempty path to the compiler flags