CMake: Finding zlib dependency broken since v1.14.5: ZLib support in HDF5 was enabled but not found

[tbeu]

Describe the bug

The following CMake file snippet works with v1.14.4.3, but fails with v1.14.5 and 1.14.6 where the configuration warning: "ZLib support in HDF5 was enabled but not found" is stated which later on results in run-time exceptions.

project(MyProject CXX)

include(FetchContent)

FetchContent_Declare(
  zlib
  GIT_REPOSITORY https://github.com/madler/zlib.git
  GIT_TAG v1.3.1
  GIT_SHALLOW TRUE
)

FetchContent_Declare(
  hdf5
  GIT_REPOSITORY https://github.com/HDFGroup/hdf5.git
#  GIT_TAG hdf5_1.14.4.3 # works
  GIT_TAG hdf5_1.14.5 #fails
  GIT_SHALLOW TRUE
)

set(ZLIB_BUILD_EXAMPLES OFF CACHE BOOL "" FORCE)
set(INSTALL_BIN_DIR ${CMAKE_INSTALL_LIBDIR} CACHE PATH "" FORCE)
set(INSTALL_LIB_DIR ${CMAKE_INSTALL_LIBDIR} CACHE PATH "" FORCE)
set(SKIP_INSTALL_ALL OFF CACHE BOOL "" FORCE)
set(SKIP_INSTALL_FILES ON CACHE BOOL "" FORCE)
set(SKIP_INSTALL_HEADERS ON CACHE BOOL "" FORCE)
set(ZLIB_FOUND ON)
set(ZLIB_USE_EXTERNAL ON)

set(HDF5_BUILD_EXAMPLES OFF CACHE BOOL "" FORCE)
set(HDF5_BUILD_HL_LIB OFF CACHE BOOL "" FORCE)
set(HDF5_BUILD_PARALLEL_TOOLS OFF CACHE BOOL "" FORCE)
set(HDF5_BUILD_TOOLS OFF CACHE BOOL "" FORCE)
set(HDF5_BUILD_UTILS OFF CACHE BOOL "" FORCE)
set(HDF5_DISABLE_COMPILER_WARNINGS ON CACHE BOOL "" FORCE)
set(HDF5_ENABLE_ALL_WARNINGS OFF CACHE BOOL "" FORCE)
set(HDF5_ENABLE_DEPRECATED_SYMBOLS OFF CACHE BOOL "" FORCE)
set(HDF5_ENABLE_NONSTANDARD_FEATURES OFF CACHE BOOL "" FORCE)
set(HDF5_ENABLE_SZIP_SUPPORT OFF CACHE BOOL "" FORCE)
set(HDF5_ENABLE_WARNINGS_AS_ERRORS OFF CACHE BOOL "" FORCE)
set(HDF5_ENABLE_Z_LIB_SUPPORT ON CACHE BOOL "" FORCE)
set(HDF5_EXPORTED_TARGETS)
set(HDF5_EXTERNALLY_CONFIGURED ON CACHE BOOL "" FORCE)
set(HDF5_INSTALL_NO_DEVELOPMENT ON CACHE BOOL "" FORCE)
set(HDF5_INSTALL_LIB_DIR ${CMAKE_INSTALL_LIBDIR} CACHE PATH "" FORCE)
set(HDF5_LIB_DEPENDENCIES zlib)
set(HDF5_TEST_CPP OFF CACHE BOOL "" FORCE)
set(HDF5_TEST_EXAMPLES OFF CACHE BOOL "" FORCE)
set(HDF5_TEST_SERIAL OFF CACHE BOOL "" FORCE)
set(HDF5_TEST_SWMR OFF CACHE BOOL "" FORCE)
set(BUILD_SHARED_LIBS OFF CACHE BOOL "" FORCE)

FetchContent_MakeAvailable(zlib)

set(ZLIB_INCLUDE_DIR ${zlib_SOURCE_DIR} ${zlib_BINARY_DIR})
set(ZLIB_INCLUDE_DIRS ${zlib_SOURCE_DIR} ${zlib_BINARY_DIR})

FetchContent_MakeAvailable(hdf5)

set(HDF5_INCLUDE_DIR "${hdf5_SOURCE_DIR}/src" "${hdf5_SOURCE_DIR}/src/H5FDsubfiling" "${hdf5_BINARY_DIR}/src")

Expected behavior
A minor release must not break the build scripts of downstream users.

Platform (please complete the following information)

• HDF5 version: v1.14.5 and v1.14.6
• OS and version: any
• Compiler and version: any
• Build system (e.g. CMake, Autotools) and version: CMake (any current version)

Additional context
Add any other context about the problem here.

[byrnHDF]

why are you setting;
set(ZLIB_FOUND ON)

[byrnHDF]

Also, to use an installed zlib, hdf5 needs: ZLIB_USE_EXTERNAL:BOOL=OFF
Yes, the name is confusing but the description is: Use External Library Building for ZLIB
This controls wether the zlib is built-in (ON) or found on the system (OFF)

[tbeu]

Thanks for the reply.

After removing set(ZLIB_FOUND ON) and ZLIB_USE_EXTERNAL negated to set(ZLIB_USE_EXTERNAL OFF) hdf5 configure finds the system zlib On Ubuntu and nothing on Win. The intent is to use the user-provided zlib instead.

[byrnHDF]

The FindZLIB.cmake module usually works best with setting the ENV(ZLIB_ROOT) to where zlib is installed. If that doesn't work and the zlib was built with CMake and provides zlib-config.cmake file, HDF5_MODULE_MODE_ZLIB:BOOL=OFF might help.

[tbeu]

I don't get hdf5 configured with zlib dependency as expected. This is just to much trial and error. Do you have a working proposal based on the example CMake code? Thanks again for your support!

[byrnHDF]

Unfortunately, I had to resort to this CMake option:
Note that if there is a problem finding the libraries, try adding the
CMake variable CMAKE_FIND_DEBUG_MODE:BOOL=ON to the command line.

[tbeu]

Given my knowledge and the high number of option combinations I have to admit that I do not have the endurance to run the tests repeatedly via CI. Obviously it is not trivial at all to update a working build script (yes, probably based on workarounds or shortcuts) from 1.14.4 to 1.14.5 or 1.14.6.

If you are curious, the whole workflow is taken from https://github.com/tbeu/ModelicaTableAdditions/blob/main/ModelicaTableAdditions/Resources/BuildProjects/CMake/test.cmake