From 1c1c256fbc6752b4f2068fe0eb734022b1044c41 Mon Sep 17 00:00:00 2001
From: Vassil Vassilev <v.g.vassilev@gmail.com>
Date: Tue, 17 Oct 2017 20:32:27 +0000
Subject: [PATCH] [cmake] Use find_package to discover zlib

This allows us to use standard cmake utilities to point to non-system zlib
locations.

Patch by Oksana Shadura and me (D39002).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@316025 91177308-0d34-0410-b5e6-96231b3b80d8
---
 cmake/config-ix.cmake      | 5 ++++-
 lib/Support/CMakeLists.txt | 2 +-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/cmake/config-ix.cmake b/cmake/config-ix.cmake
index 7f33591de0c..c90f2d836c8 100644
--- a/cmake/config-ix.cmake
+++ b/cmake/config-ix.cmake
@@ -132,7 +132,10 @@ endif()
 # like strlen, leading to false positives.
 if( NOT PURE_WINDOWS AND NOT LLVM_USE_SANITIZER MATCHES "Memory.*")
   if (LLVM_ENABLE_ZLIB)
-    check_library_exists(z compress2 "" HAVE_LIBZ)
+    find_package(ZLIB REQUIRED)
+    if (ZLIB_FOUND)
+      set(HAVE_LIBZ 1)
+    endif()
   else()
     set(HAVE_LIBZ 0)
   endif()
diff --git a/lib/Support/CMakeLists.txt b/lib/Support/CMakeLists.txt
index 56aaf10ec2c..5dcb5e58af4 100644
--- a/lib/Support/CMakeLists.txt
+++ b/lib/Support/CMakeLists.txt
@@ -22,7 +22,7 @@ elseif( CMAKE_HOST_UNIX )
   endif()
   set(system_libs ${system_libs} ${LLVM_PTHREAD_LIB})
   if ( LLVM_ENABLE_ZLIB AND HAVE_LIBZ )
-    set(system_libs ${system_libs} z)
+    set(system_libs ${system_libs} ${ZLIB_LIBRARIES})
   endif()
   if( UNIX AND NOT (BEOS OR HAIKU) )
     set(system_libs ${system_libs} m)
-- 
2.40.0