[debugserver ] Un-conditionalize use of libcompression

[JDevlieghere]

Summary

Jason removed the include guards in 681f6c2f552fb9b57380f4bfd453e1fc9b6a099e. This removes the corresponding CMake logic.

[jasonmolenda]

I think we only support building debugserver on macOS systems that have libcompression. Was there a configuration where this resulted in an error? lldb needs to test for libcompression and use it if available, but with debugserver we assume it is available iirc. I'm fine with the patch, but I'm curious how it came up. It used to be tested before use etc but I removed that a couple of years ago when our minimum deployment target was high enough that it was always available.

[jasonmolenda]

fwiw,

commit 681f6c2f552fb9b57380f4bfd453e1fc9b6a099e
Author: Jason Molenda <[e-mail]>
Date:   Tue Dec 18 22:21:48 2018 +0000

    Un-conditionalize use of libcompression.  debugserver only builds
    on Darwin systems and libcompression has been in the OS for over
    three years.

[JDevlieghere]

That also works for me, but then let's remove the corresponding logic in CMake as well.

[jasonmolenda]

Sounds good. I think it's test-and-use for lldb, and debugserver ended up structure the same way.

lldb/tools/debugserver/source/CMakeLists.txt

 )
 
 # You can only debug arm64e processes using an arm64e debugserver.
 option(LLDB_ENABLE_ARM64E_DEBUGSERVER "Build debugserver for arm64 and arm64e" OFF)
 if (BUILDING_FOR_ARM64_OSX AND LLDB_ENABLE_ARM64E_DEBUGSERVER)
   set(CMAKE_OSX_ARCHITECTURES "arm64;arm64e")
 endif ()
 
-check_library_exists(compression compression_encode_buffer "" HAVE_LIBCOMPRESSION)
-
 find_library(SECURITY_LIBRARY Security)
 
 add_subdirectory(MacOSX)
 
 set(LLDB_CODESIGN_IDENTITY "" CACHE STRING
     "Identity override for debugserver; see 'Code Signing on macOS' in the documentation (Darwin only)")
 
 get_debugserver_codesign_identity(debugserver_codesign_identity)
 
 # Override locally, so the identity is used for targets created in this scope.
 set(LLVM_CODESIGNING_IDENTITY ${debugserver_codesign_identity})
 
 # Use the same identity later in the test suite.
 set_property(GLOBAL PROPERTY
   LLDB_DEBUGSERVER_CODESIGN_IDENTITY ${debugserver_codesign_identity})
 
 if(APPLE)
+  set(LIBCOMPRESSION compression)
   if(APPLE_EMBEDDED)
     find_library(BACKBOARD_LIBRARY BackBoardServices
       PATHS ${CMAKE_OSX_SYSROOT}/System/Library/PrivateFrameworks)
     find_library(FRONTBOARD_LIBRARY FrontBoardServices
       PATHS ${CMAKE_OSX_SYSROOT}/System/Library/PrivateFrameworks)
     find_library(SPRINGBOARD_LIBRARY SpringBoardServices
       PATHS ${CMAKE_OSX_SYSROOT}/System/Library/PrivateFrameworks)
     find_library(MOBILESERVICES_LIBRARY MobileCoreServices
       PATHS ${CMAKE_OSX_SYSROOT}/System/Library/PrivateFrameworks)
     find_library(LOCKDOWN_LIBRARY lockdown)
     if (APPLE_EMBEDDED STREQUAL "watchos")
       find_library(CAROUSELSERVICES_LIBRARY CarouselServices
         PATHS ${CMAKE_OSX_SYSROOT}/System/Library/PrivateFrameworks)
     endif()
 
     if(NOT BACKBOARD_LIBRARY)
       set(SKIP_TEST_DEBUGSERVER ON CACHE BOOL "" FORCE)
     endif()
   endif()
 endif()
 
-if(HAVE_LIBCOMPRESSION)
-  set(LIBCOMPRESSION compression)
-endif()
-
 if(LLDB_USE_ENTITLEMENTS)
   if(APPLE_EMBEDDED)
     set(entitlements ${DEBUGSERVER_RESOURCE_DIR}/debugserver-entitlements.plist)
   else()
     if (LLDB_USE_PRIVATE_ENTITLEMENTS)
       set(entitlements ${DEBUGSERVER_RESOURCE_DIR}/debugserver-macosx-private-entitlements.plist)
     else()
       set(entitlements ${DEBUGSERVER_RESOURCE_DIR}/debugserver-macosx-entitlements.plist)
target_link_libraries(lldbDebugserverCommon
                       ${MOBILESERVICES_LIBRARY}
                       ${LOCKDOWN_LIBRARY}
                       ${CAROUSELSERVICES_LIBRARY}
                       lldbDebugserverArchSupport
                       ${FOUNDATION_LIBRARY}
                       ${SECURITY_LIBRARY}
                       ${LIBCOMPRESSION}
                       ${ENERGY_LIBRARY})
-if(HAVE_LIBCOMPRESSION)
-  set_property(TARGET lldbDebugserverCommon APPEND PROPERTY
-                COMPILE_DEFINITIONS HAVE_LIBCOMPRESSION)
-endif()
 add_lldb_tool(debugserver ADD_TO_FRAMEWORK
   debugserver.cpp
   LINK_LIBS lldbDebugserverCommon
   ENTITLEMENTS ${entitlements}
 )
 
 # Workaround for Xcode-specific code-signing behavior:
 # The XCODE_ATTRIBUTE_CODE_SIGN_IDENTITY option causes debugserver to be copied
if(APPLE_EMBEDDED)
   add_lldb_library(lldbDebugserverCommon_NonUI ${lldbDebugserverCommonSources})
   target_link_libraries(lldbDebugserverCommon_NonUI
                       INTERFACE ${COCOA_LIBRARY}
                       ${CORE_FOUNDATION_LIBRARY}
                       ${FOUNDATION_LIBRARY}
                       lldbDebugserverArchSupport
                       ${SECURITY_LIBRARY}
                       ${LIBCOMPRESSION})
-  if(HAVE_LIBCOMPRESSION)
-    set_property(TARGET lldbDebugserverCommon_NonUI APPEND PROPERTY
-                  COMPILE_DEFINITIONS HAVE_LIBCOMPRESSION)
-  endif()
 
   add_lldb_tool(debugserver-nonui
     debugserver.cpp
 
     LINK_LIBS
       lldbDebugserverCommon_NonUI
 
     ENTITLEMENTS
       ${entitlements}
     )
 endif()