Look in build directory for zlib.pc in CMakeLists.txt.

CMakeLists.txt

@@ -75,8 +75,9 @@ if(NOT CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_CURRENT_BINARY_DIR)
   endif()
 endif()
 
+set(ZLIB_PC ${CMAKE_CURRENT_BINARY_DIR}/zlib.pc)
 configure_file( ${CMAKE_CURRENT_SOURCE_DIR}/zlib.pc.cmakein
-		${CMAKE_CURRENT_BINARY_DIR}/zlib.pc @ONLY)
+		${ZLIB_PC} @ONLY)
 configure_file(	${CMAKE_CURRENT_SOURCE_DIR}/zconf.h.cmakein
 		${CMAKE_CURRENT_BINARY_DIR}/zconf.h @ONLY)
 include_directories(${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_SOURCE_DIR})
@@ -184,7 +185,7 @@ if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )
     install(FILES zlib.3 DESTINATION "${INSTALL_MAN_DIR}/man3")
 endif()
 if(NOT SKIP_INSTALL_FILES AND NOT SKIP_INSTALL_ALL )
-    install(FILES zlib.pc DESTINATION "${INSTALL_PKGCONFIG_DIR}")
+    install(FILES ${ZLIB_PC} DESTINATION "${INSTALL_PKGCONFIG_DIR}")
 endif()
 
 #============================================================================