- make the symbol check optional

Author: fbergmann

CMakeModules/FindZLIB.cmake

@@ -1,4 +1,4 @@
-# Copyright (C) 2022 by Pedro Mendes, Rector and Visitors of the 
+# Copyright (C) 2022 - 2025 by Pedro Mendes, Rector and Visitors of the 
 # University of Virginia, University of Heidelberg, and University 
 # of Connecticut School of Medicine. 
 # All rights reserved. 
@@ -31,38 +31,43 @@ if (NOT (ZLIB_INCLUDE_DIR AND ZLIB_LIBRARY) OR NOT ZLIB_FOUND)
     find_path(ZLIB_INCLUDE_DIR zlib.h zlib/zlib.h
 	    PATHS $ENV{ZLIB_DIR}/include
 	          $ENV{ZLIB_DIR}
-            ${${_PROJECT_DEPENDENCY_DIR}}/include
+	          ${${_PROJECT_DEPENDENCY_DIR}}/include
 	          ~/Library/Frameworks
 	          /Library/Frameworks
 	          /sw/include        # Fink
 	          /opt/local/include # MacPorts
 	          /opt/csw/include   # Blastwave
 	          /opt/include
 	          /usr/freeware/include
-            NO_DEFAULT_PATH)
+	          CMAKE_FIND_ROOT_PATH_BOTH
+	          NO_DEFAULT_PATH)
 
     if (NOT ZLIB_INCLUDE_DIR)
-        find_path(ZLIB_INCLUDE_DIR zlib.h zlib/zlib.h)
+        find_path(ZLIB_INCLUDE_DIR zlib.h zlib/zlib.h
+        CMAKE_FIND_ROOT_PATH_BOTH )
     endif ()
 
     find_library(ZLIB_LIBRARY 
-	    NAMES zdll.lib z zlib.lib libzlib zlib libzlib.a 
+	    NAMES zdll.lib z zlib.lib libzlib zlib libzlib.a libzdll.a
 	    PATHS $ENV{ZLIB_DIR}/lib
 	          $ENV{ZLIB_DIR}/lib-dbg
 	          $ENV{ZLIB_DIR}
-            ${${_PROJECT_DEPENDENCY_DIR}}/${CMAKE_INSTALL_LIBDIR}
-            ${${_PROJECT_DEPENDENCY_DIR}}
+              ${${_PROJECT_DEPENDENCY_DIR}}/${CMAKE_INSTALL_LIBDIR}
+              ${${_PROJECT_DEPENDENCY_DIR}}/lib
+              ${${_PROJECT_DEPENDENCY_DIR}}
 	          ~/Library/Frameworks
 	          /Library/Frameworks
 	          /sw/lib        # Fink
 	          /opt/local/lib # MacPorts
 	          /opt/csw/lib   # Blastwave
 	          /opt/lib
 	          /usr/freeware/lib64
+              CMAKE_FIND_ROOT_PATH_BOTH
              NO_DEFAULT_PATH)
 
     if (NOT ZLIB_LIBRARY)
-        find_library(ZLIB_LIBRARY NAMES zdll.lib z zlib.lib libzlib zlib libzlib.a)
+        find_library(ZLIB_LIBRARY NAMES zdll.lib z zlib.lib libzlib zlib libzlib.a libzdll.a
+        CMAKE_FIND_ROOT_PATH_BOTH )
     endif ()
 
     if (NOT WIN32)
@@ -77,6 +82,22 @@ if (NOT (ZLIB_INCLUDE_DIR AND ZLIB_LIBRARY) OR NOT ZLIB_FOUND)
         endif (PC_ZLIB_FOUND)
     endif (NOT WIN32)
 
+    
+    # make sure that we have a valid zip library
+    if (ZLIB_CHECK_FOR_SYMBOLS)
+    file(TO_CMAKE_PATH "${ZLIB_LIBRARY}" LIBZ_CMAKE_PATH)
+    include(CheckLibraryExists)
+    check_library_exists("${LIBZ_CMAKE_PATH}" "gzopen" "" LIBZ_FOUND_SYMBOL)
+
+    if(NOT LIBZ_FOUND_SYMBOL AND UNIX)
+        message(WARNING
+                "The chosen zlib library does not appear to be valid because it is
+    missing certain required symbols. Please check that ${ZLIB_LIBRARY} is
+    the correct zlib library. For details about the error, please see
+    CMakeError.log or CMakeConfigureLog.yaml in the build directory.")
+    endif()
+    endif() # Check for symbols
+
     mark_as_advanced(ZLIB_INCLUDE_DIR ZLIB_LIBRARY)
 
 endif () # Check for cached values