We've already added ZLIB_LIBRARIES to LIBGIT2_LIBS so don't also add the z library (libgit2/libgit2#5079).

Author: dbrnz

src/CMakeLists.txt

@@ -327,12 +327,6 @@ IF(NOT USE_BUNDLED_ZLIB)
 	IF(ZLIB_FOUND)
 		LIST(APPEND LIBGIT2_SYSTEM_INCLUDES ${ZLIB_INCLUDE_DIRS})
 		LIST(APPEND LIBGIT2_LIBS ${ZLIB_LIBRARIES})
-		IF(APPLE OR CMAKE_SYSTEM_NAME MATCHES "FreeBSD")
-			LIST(APPEND LIBGIT2_LIBS "z")
-			LIST(APPEND LIBGIT2_PC_LIBS "-lz")
-		ELSE()
-			LIST(APPEND LIBGIT2_PC_REQUIRES "zlib")
-		ENDIF()
 		ADD_FEATURE_INFO(zlib ON "using system zlib")
 	ELSE()
 		MESSAGE(STATUS "zlib was not found; using bundled 3rd-party sources." )