From c41281ad3af420bcfe4afae6acdbe95039290525 Mon Sep 17 00:00:00 2001 From: Thomas Rast Date: Wed, 19 Jun 2013 13:36:59 +0200 Subject: [PATCH] CMakeLists: fix zlib linker setup b53671a (Search for zlib unconditional, 2012-12-18) changed things around to always (even on windows, that's what the subject refers to) call FIND_PACKAGE(ZLIB). However, it did not correctly handle the case where ZLIB_LIBRARY is cached, either by the user setting it manually or by an earlier search. In that case, the IF(ZLIB_FOUND) would not trigger (that variable is not cached) and we'd instead use the built-in version. 000e689 (CMake: don't try to use bundled zlib when the system's path is in the cache, 2013-05-12) tried to fix that, but it actually made the problem worse: now with ZLIB_LIBRARY cached, _neither_ of the blocks would execute, resulting in a linker error for me when trying to build such a doubly-configured setup. To fix the issue, we just trust CMake to do the right thing. If ZLIB_LIBRARY is set (either from user or cache) then the find_library in FindZLIB.cmake will use that instead of searching again. So we can unconditionally (for real this time) call FIND_PACKAGE(ZLIB), and just check its result. --- CMakeLists.txt | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/CMakeLists.txt b/CMakeLists.txt index bdc46d0b3..34d56b3fa 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -136,17 +136,15 @@ IF(WIN32 OR AMIGA) ENDIF() # Optional external dependency: zlib -IF(NOT ZLIB_LIBRARY) - # It's optional, but FIND_PACKAGE gives a warning that looks more like an - # error. - FIND_PACKAGE(ZLIB QUIET) -ENDIF() +# It's optional, but FIND_PACKAGE gives a warning that looks more like an +# error. +FIND_PACKAGE(ZLIB QUIET) IF (ZLIB_FOUND) INCLUDE_DIRECTORIES(${ZLIB_INCLUDE_DIRS}) LINK_LIBRARIES(${ZLIB_LIBRARIES}) # Fake the message CMake would have shown MESSAGE("-- Found zlib: ${ZLIB_LIBRARY}") -ELSEIF (NOT ZLIB_LIBRARY) +ELSE() MESSAGE( "zlib was not found; using bundled 3rd-party sources." ) INCLUDE_DIRECTORIES(deps/zlib) ADD_DEFINITIONS(-DNO_VIZ -DSTDC -DNO_GZIP)