CMake cleanup

Author: srimanachanta

CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.15)
+cmake_minimum_required(VERSION 3.24)
 project(samseg LANGUAGES C CXX)
 
 include(FetchContent)
@@ -8,23 +8,12 @@ if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
   set(CMAKE_BUILD_TYPE "Release" CACHE STRING "Default build type" FORCE)
 endif()
 
-find_package(pybind11 QUIET)
-if(NOT pybind11_FOUND)
-  message(STATUS "pybind11 not found, fetching from source...")
-  FetchContent_Declare(pybind11
-    GIT_REPOSITORY https://github.com/pybind/pybind11.git
-    GIT_TAG        stable
-    GIT_SHALLOW    TRUE
-  )
-  FetchContent_MakeAvailable(pybind11)
-endif()
-
-find_package(ITK QUIET)
-
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)
 
+option(PROFILING "Enable profiling with -pg" OFF)
+
 # Warning flags applied only to our own targets via INTERFACE library
 # so that third-party dependencies (ITK, GDCM, etc.) are not affected.
 add_library(samseg_warnings INTERFACE)
@@ -33,21 +22,22 @@ if(CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "GNU"
     -Wall -Wextra
     -Wno-sign-compare -Wno-unused-parameter
   )
+elseif(MSVC)
+  target_compile_options(samseg_warnings INTERFACE /W3)
 endif()
 
-if(APPLE)
-  add_link_options(-dead_strip)
-  if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
-    add_link_options(-static-libgcc)
-  endif()
-elseif(NOT WIN32)
-  add_compile_options(-fdata-sections -ffunction-sections)
-  add_link_options(-Wl,--gc-sections)
+if(PROFILING AND NOT MSVC)
+  target_compile_options(samseg_warnings INTERFACE -pg)
+  target_link_options(samseg_warnings INTERFACE -pg)
 endif()
 
-if(PROFILING)
-  add_compile_options(-pg)
-  add_link_options(-pg)
+# Binary size optimization flags, applied per-target via INTERFACE library
+add_library(samseg_linkopt INTERFACE)
+if(APPLE)
+  target_link_options(samseg_linkopt INTERFACE -Wl,-dead_strip)
+elseif(NOT WIN32)
+  target_compile_options(samseg_linkopt INTERFACE -fdata-sections -ffunction-sections)
+  target_link_options(samseg_linkopt INTERFACE -Wl,--gc-sections)
 endif()
 
 add_subdirectory(gems)

gems/CMakeLists.txt

@@ -1,6 +1,8 @@
-if(NOT ITK_FOUND)
-  find_package(ITK 5.4.5 QUIET)
-endif()
+# ITK: try local install first, fetch from source if unavailable.
+# FIND_PACKAGE_ARGS is not used here because ITK 5.4.x requires
+# include(${ITK_USE_FILE}) for factory registration, which is only
+# set by find_package — not by FetchContent's add_subdirectory path.
+find_package(ITK 5.4.5 QUIET)
 if(NOT ITK_FOUND)
   message(STATUS "ITK not found, fetching from source (v5.4.5)...")
   FetchContent_Declare(ITK
@@ -13,15 +15,14 @@ if(NOT ITK_FOUND)
   set(BUILD_EXAMPLES OFF CACHE BOOL "" FORCE)
   FetchContent_MakeAvailable(ITK)
   set(ITK_DIR "${itk_BINARY_DIR}" CACHE PATH "" FORCE)
+  find_package(ITK REQUIRED)
 endif()
 
-# Per ITK Software Guide §2.5
-find_package(ITK REQUIRED)
+# UseITK.cmake handles factory registration and required compiler flags.
+# Still required with ITK 5.4.x which does not export namespace targets.
 include(${ITK_USE_FILE})
 
-if(NOT ZLIB_FOUND)
-  find_package(ZLIB QUIET)
-endif()
+find_package(ZLIB QUIET)
 if(NOT ZLIB_FOUND)
   # ITK exports its bundled zlib-ng as a target named "zlib"
   if(TARGET zlib)
@@ -98,18 +99,10 @@ function(configure_gems_target target)
     ${ITK_INCLUDE_DIRS}
   )
   target_link_libraries(${target}
-    PRIVATE samseg_warnings ${ZLIB_LIBRARIES}
+    PRIVATE samseg_warnings samseg_linkopt ${ZLIB_LIBRARIES}
     PUBLIC ${ITK_LIBRARIES}
   )
 
-  if(CMAKE_SYSTEM_PROCESSOR MATCHES "(x86_64|AMD64|i[3-6]86)")
-    if(MSVC)
-      target_compile_options(${target} PRIVATE /arch:SSE2)
-    else()
-      target_compile_options(${target} PRIVATE -msse2 -mfpmath=sse)
-    endif()
-  endif()
-
   if(DEFINED ENV{GEMS_DEBUG_CXXFLAG})
     message(WARNING "additional gems debug cxxflags: $ENV{GEMS_DEBUG_CXXFLAG}")
     target_compile_options(${target} PRIVATE $ENV{GEMS_DEBUG_CXXFLAG})

samseg/gems/_cxx/CMakeLists.txt

@@ -1,3 +1,13 @@
+set(PYBIND11_FINDPYTHON ON)
+
+FetchContent_Declare(pybind11
+  GIT_REPOSITORY https://github.com/pybind/pybind11.git
+  GIT_TAG        v2.13.6
+  GIT_SHALLOW    TRUE
+  FIND_PACKAGE_ARGS QUIET
+)
+FetchContent_MakeAvailable(pybind11)
+
 pybind11_add_module(gemsbindings
   module.cxx
   pyKvlCalculator.cxx
@@ -9,13 +19,15 @@ pybind11_add_module(gemsbindings
   pyKvlAffineRegistration.cxx
 )
 
-target_include_directories(gemsbindings PRIVATE ${CMAKE_CURRENT_SOURCE_DIR} ${ITK_INCLUDE_DIRS})
-target_link_libraries(gemsbindings PRIVATE samseg_warnings kvlGEMSCommon ${ITK_LIBRARIES})
+target_include_directories(gemsbindings PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
+target_link_libraries(gemsbindings PRIVATE samseg_warnings samseg_linkopt kvlGEMSCommon)
 
 # pybind11 debug builds produce objects too large for the linker with -g
-target_compile_options(gemsbindings PRIVATE
-  $<$<CONFIG:Debug>:-g0>
-  $<$<CONFIG:RelWithDebInfo>:-g0>
-)
+if(NOT MSVC)
+  target_compile_options(gemsbindings PRIVATE
+    $<$<CONFIG:Debug>:-g0>
+    $<$<CONFIG:RelWithDebInfo>:-g0>
+  )
+endif()
 
 install(TARGETS gemsbindings LIBRARY DESTINATION samseg/gems)