cmake configuration fails with custom provided zlib

[malytomas]

I am using curl with add_subdirectory in cmake. I have custom zlib (zlib-ng actually), and I provide target ZLIB::ZLIB as an interface library, which has dependency on another target. The target ZLIB::ZLIB does not have (and cannot have) the property LOCATION.

Unfortunately, recent changes to curl cmake:

curl/CMakeLists.txt

Line 1416 in a158a09

get_target_property(_lib "${_lib}" LOCATION)

generates this error in my setup:

-- Enabled features: SSL IPv6 libz AsynchDNS SSPI SPNEGO Kerberos NTLM
-- Enabled protocols: HTTP HTTPS
-- Enabled SSL backends: WinSSL
CMake Error at externals/curl/curl/CMakeLists.txt:1416 (get_target_property):
  INTERFACE_LIBRARY targets may only have whitelisted properties.  The
  property "LOCATION" is not allowed.

CMake Warning at externals/curl/curl/CMakeLists.txt:1418 (message):
  Bad lib in library list: ZLIB::ZLIB

The code does not seem to have any effect and commenting it worked for me.

foreach(_lib ${CMAKE_C_IMPLICIT_LINK_LIBRARIES} ${CURL_LIBS})
  #if(TARGET "${_lib}")
  #  set(_libname "${_lib}")
  #  get_target_property(_lib "${_lib}" LOCATION)
  #  if(NOT _lib)
  #    message(WARNING "Bad lib in library list: ${_libname}")
  #    continue()
  #  endif()
  #endif()
  if(_lib MATCHES ".*/.*" OR _lib MATCHES "^-")
    set(LIBCURL_LIBS          "${LIBCURL_LIBS} ${_lib}")
  else()
    set(LIBCURL_LIBS          "${LIBCURL_LIBS} -l${_lib}")
  endif()
endforeach()

curl/libcurl version

commit 2bf7d1b

operating system

Windows 10
cmake version 3.17.3
(msvc 16.6.1)

[Lekensteyn]

The code was added via a158a09 to avoid adding stuff like OpenSSL::SSL to the generated pkg-config (.pc) file. For a configuration such as yours, I guess it is better to omit the library from the .pc file and assume the integrator adds the appropriate linking commands.

Can you test the upcoming patch?

[malytomas]

Yes this is working for me. Thanks.