[vcpkg-cmake] Add check for unused cmake variables

docs/maintainers/ports/vcpkg-cmake/vcpkg_cmake_configure.md

@@ -18,6 +18,8 @@ vcpkg_cmake_configure(
         <configure-setting>...]
     [OPTIONS_DEBUG
         <configure-setting>...]
+    [MAYBE_UNUSED_VARIABLES
+        <variable-name>...]
 )
 ```
 
@@ -56,6 +58,11 @@ By default, this function adds flags to `CMAKE_C_FLAGS` and `CMAKE_CXX_FLAGS`
 which set the default character set to utf-8 for MSVC.
 If the library sets its own code page, pass the `NO_CHARSET_FLAG` option.
 
+This function makes certain that all options passed in are used by the
+underlying CMake build system. If there are options that might be unused,
+perhaps on certain platforms, pass those variable names to
+`MAYBE_UNUSED_VARIABLES`.
+
 `LOGFILE_BASE` is used to set the base of the logfile names;
 by default, this is `config`, and thus the logfiles end up being something like
 `config-x86-windows-dbg.log`. You can set it to anything you like;

docs/maintainers/vcpkg_configure_cmake.md

@@ -17,6 +17,7 @@ vcpkg_configure_cmake(
     [OPTIONS <-DUSE_THIS_IN_ALL_BUILDS=1>...]
     [OPTIONS_RELEASE <-DOPTIMIZE=1>...]
     [OPTIONS_DEBUG <-DDEBUGGABLE=1>...]
+    [MAYBE_UNUSED_VARIABLES <option-name>...]
 )
 ```
 
@@ -55,6 +56,9 @@ Additional options passed to CMake during the Release configuration. These are i
 ### OPTIONS_DEBUG
 Additional options passed to CMake during the Debug configuration. These are in addition to `OPTIONS`.
 
+### MAYBE_UNUSED_VARIABLES
+Any CMake variables which are explicitly passed in, but which may not be used on all platforms.
+
 ### LOGNAME
 Name of the log to write the output of the configure call to.
 

ports/vcpkg-cmake/vcpkg_cmake_configure.cmake

@@ -17,6 +17,8 @@ vcpkg_cmake_configure(
         <configure-setting>...]
     [OPTIONS_DEBUG
         <configure-setting>...]
+    [MAYBE_UNUSED_VARIABLES
+        <variable-name>...]
 )
 ```
 
@@ -55,6 +57,11 @@ By default, this function adds flags to `CMAKE_C_FLAGS` and `CMAKE_CXX_FLAGS`
 which set the default character set to utf-8 for MSVC.
 If the library sets its own code page, pass the `NO_CHARSET_FLAG` option.
 
+This function makes certain that all options passed in are used by the
+underlying CMake build system. If there are options that might be unused,
+perhaps on certain platforms, pass those variable names to
+`MAYBE_UNUSED_VARIABLES`.
+
 `LOGFILE_BASE` is used to set the base of the logfile names;
 by default, this is `config`, and thus the logfiles end up being something like
 `config-x86-windows-dbg.log`. You can set it to anything you like;
@@ -88,7 +95,7 @@ function(vcpkg_cmake_configure)
     cmake_parse_arguments(PARSE_ARGV 0 "arg"
         "PREFER_NINJA;DISABLE_PARALLEL_CONFIGURE;WINDOWS_USE_MSBUILD;NO_CHARSET_FLAG"
         "SOURCE_PATH;GENERATOR;LOGFILE_BASE"
-        "OPTIONS;OPTIONS_DEBUG;OPTIONS_RELEASE"
+        "OPTIONS;OPTIONS_DEBUG;OPTIONS_RELEASE;MAYBE_UNUSED_VARIABLES"
     )
 
     if(DEFINED CACHE{Z_VCPKG_CMAKE_GENERATOR})
@@ -102,9 +109,19 @@ function(vcpkg_cmake_configure)
         message(FATAL_ERROR "SOURCE_PATH must be set")
     endif()
     if(NOT DEFINED arg_LOGFILE_BASE)
-        set(arg_LOGFILE_BASE "config")
+        set(arg_LOGFILE_BASE "config-${TARGET_TRIPLET}")
     endif()
 
+    set(manually_specified_variables "")
+    foreach(option IN LISTS arg_OPTIONS arg_OPTIONS_RELEASE arg_OPTIONS_DEBUG)
+        if(option MATCHES "^-D([^:=]*)[:=]")
+            list(APPEND manually_specified_variables "${CMAKE_MATCH_1}")
+        endif()
+    endforeach()
+    list(REMOVE_DUPLICATES manually_specified_variables)
+    list(REMOVE_ITEM manually_specified_variables ${arg_MAYBE_UNUSED_VARIABLES})
+    debug_message("manually specified variables: ${manually_specified_variables}")
+
     if(CMAKE_HOST_WIN32)
         if(DEFINED ENV{PROCESSOR_ARCHITEW6432})
             set(host_architecture "$ENV{PROCESSOR_ARCHITEW6432}")
@@ -362,8 +379,11 @@ function(vcpkg_cmake_configure)
         vcpkg_execute_required_process(
             COMMAND ninja -v
             WORKING_DIRECTORY "${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-rel/vcpkg-parallel-configure"
-            LOGNAME "${arg_LOGFILE_BASE}-${TARGET_TRIPLET}"
+            LOGNAME "${arg_LOGFILE_BASE}"
         )
+        list(APPEND config_logs
+            "${CURRENT_BUILDTREES_DIR}/${arg_LOGFILE_BASE}-out.log"
+            "${CURRENT_BUILDTREES_DIR}/${arg_LOGFILE_BASE}-err.log")
     else()
         if(NOT DEFINED VCPKG_BUILD_TYPE OR VCPKG_BUILD_TYPE STREQUAL "debug")
             message(STATUS "Configuring ${TARGET_TRIPLET}-dbg")
@@ -377,8 +397,11 @@ function(vcpkg_cmake_configure)
                     "-DCMAKE_BUILD_TYPE=Debug"
                     "-DCMAKE_INSTALL_PREFIX=${CURRENT_PACKAGES_DIR}/debug"
                 WORKING_DIRECTORY "${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-dbg"
-                LOGNAME "${arg_LOGFILE_BASE}-${TARGET_TRIPLET}-dbg"
+                LOGNAME "${arg_LOGFILE_BASE}-dbg"
             )
+            list(APPEND config_logs
+                "${CURRENT_BUILDTREES_DIR}/${arg_LOGFILE_BASE}-dbg-out.log"
+                "${CURRENT_BUILDTREES_DIR}/${arg_LOGFILE_BASE}-dbg-err.log")
         endif()
 
         if(NOT DEFINED VCPKG_BUILD_TYPE OR VCPKG_BUILD_TYPE STREQUAL "release")
@@ -395,7 +418,42 @@ function(vcpkg_cmake_configure)
                 WORKING_DIRECTORY "${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-rel"
                 LOGNAME "${arg_LOGFILE_BASE}-rel"
             )
+            list(APPEND config_logs
+                "${CURRENT_BUILDTREES_DIR}/${arg_LOGFILE_BASE}-rel-out.log"
+                "${CURRENT_BUILDTREES_DIR}/${arg_LOGFILE_BASE}-rel-err.log")
+        endif()
+    endif()
+
+    set(all_unused_variables)
+    foreach(config_log IN LISTS config_logs)
+        if(NOT EXISTS "${config_log}")
+            continue()
         endif()
+        file(READ "${config_log}" log_contents)
+        debug_message("Reading configure log ${config_log}...")
+        if(NOT log_contents MATCHES "Manually-specified variables were not used by the project:\n\n((    [^\n]*\n)*)")
+            continue()
+        endif()
+        string(STRIP "${CMAKE_MATCH_1}" unused_variables) # remove leading `    ` and trailing `\n`
+        string(REPLACE "\n    " ";" unused_variables "${unused_variables}")
+        debug_message("unused variables: ${unused_variables}")
+        foreach(unused_variable IN LISTS unused_variables)
+            if(unused_variable IN_LIST manually_specified_variables)
+                debug_message("manually specified unused variable: ${unused_variable}")
+                list(APPEND all_unused_variables "${unused_variable}")
+            else()
+                debug_message("unused variable (not manually specified): ${unused_variable}")
+            endif()
+        endforeach()
+    endforeach()
+
+    if(DEFINED all_unused_variables)
+        list(REMOVE_DUPLICATES all_unused_variables)
+        list(JOIN all_unused_variables "\n    " all_unused_variables)
+        message(WARNING "The following variables are not used in CMakeLists.txt:
+    ${all_unused_variables}
+Please recheck them and remove the unnecessary options from the `vcpkg_cmake_configure` call.
+If these options should still be passed for whatever reason, please use the `MAYBE_UNUSED_VARIABLES` argument.")
     endif()
 
     set(Z_VCPKG_CMAKE_GENERATOR "${generator}" CACHE INTERNAL "The generator which was used to configure CMake.")

scripts/cmake/vcpkg_configure_cmake.cmake

@@ -15,6 +15,7 @@ vcpkg_configure_cmake(
     [OPTIONS <-DUSE_THIS_IN_ALL_BUILDS=1>...]
     [OPTIONS_RELEASE <-DOPTIMIZE=1>...]
     [OPTIONS_DEBUG <-DDEBUGGABLE=1>...]
+    [MAYBE_UNUSED_VARIABLES <option-name>...]
 )
 ```
 
@@ -53,6 +54,9 @@ Additional options passed to CMake during the Release configuration. These are i
 ### OPTIONS_DEBUG
 Additional options passed to CMake during the Debug configuration. These are in addition to `OPTIONS`.
 
+### MAYBE_UNUSED_VARIABLES
+Any CMake variables which are explicitly passed in, but which may not be used on all platforms.
+
 ### LOGNAME
 Name of the log to write the output of the configure call to.
 
@@ -73,9 +77,9 @@ function(vcpkg_configure_cmake)
     endif()
 
     cmake_parse_arguments(PARSE_ARGV 0 arg
-        "PREFER_NINJA;DISABLE_PARALLEL_CONFIGURE;NO_CHARSET_FLAG"
+        "PREFER_NINJA;DISABLE_PARALLEL_CONFIGURE;NO_CHARSET_FLAG;Z_VCPKG_IGNORE_UNUSED_VARIABLES"
         "SOURCE_PATH;GENERATOR;LOGNAME"
-        "OPTIONS;OPTIONS_DEBUG;OPTIONS_RELEASE"
+        "OPTIONS;OPTIONS_DEBUG;OPTIONS_RELEASE;MAYBE_UNUSED_VARIABLES"
     )
 
     if(NOT VCPKG_PLATFORM_TOOLSET)
@@ -87,6 +91,18 @@ function(vcpkg_configure_cmake)
         set(arg_LOGNAME config-${TARGET_TRIPLET})
     endif()
 
+    set(manually_specified_variables "")
+    if(NOT arg_Z_VCPKG_IGNORE_UNUSED_VARIABLES)
+        foreach(option IN LISTS arg_OPTIONS arg_OPTIONS_RELEASE arg_OPTIONS_DEBUG)
+            if(option MATCHES "^-D([^:=]*)[:=]")
+                list(APPEND manually_specified_variables "${CMAKE_MATCH_1}")
+            endif()
+        endforeach()
+        list(REMOVE_DUPLICATES manually_specified_variables)
+        list(REMOVE_ITEM manually_specified_variables ${arg_MAYBE_UNUSED_VARIABLES})
+        debug_message("manually specified variables: ${manually_specified_variables}")
+    endif()
+
     if(CMAKE_HOST_WIN32)
         if(DEFINED ENV{PROCESSOR_ARCHITEW6432})
             set(arg_HOST_ARCHITECTURE $ENV{PROCESSOR_ARCHITEW6432})
@@ -325,6 +341,10 @@ function(vcpkg_configure_cmake)
             WORKING_DIRECTORY ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-rel/vcpkg-parallel-configure
             LOGNAME ${arg_LOGNAME}
         )
+
+        list(APPEND config_logs
+            "${CURRENT_BUILDTREES_DIR}/${arg_LOGNAME}-out.log"
+            "${CURRENT_BUILDTREES_DIR}/${arg_LOGNAME}-err.log")
     else()
         if(NOT DEFINED VCPKG_BUILD_TYPE OR VCPKG_BUILD_TYPE STREQUAL "debug")
             message(STATUS "Configuring ${TARGET_TRIPLET}-dbg")
@@ -334,6 +354,9 @@ function(vcpkg_configure_cmake)
                 WORKING_DIRECTORY ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-dbg
                 LOGNAME ${arg_LOGNAME}-dbg
             )
+            list(APPEND config_logs
+                "${CURRENT_BUILDTREES_DIR}/${arg_LOGNAME}-dbg-out.log"
+                "${CURRENT_BUILDTREES_DIR}/${arg_LOGNAME}-dbg-err.log")
         endif()
 
         if(NOT DEFINED VCPKG_BUILD_TYPE OR VCPKG_BUILD_TYPE STREQUAL "release")
@@ -344,7 +367,44 @@ function(vcpkg_configure_cmake)
                 WORKING_DIRECTORY ${CURRENT_BUILDTREES_DIR}/${TARGET_TRIPLET}-rel
                 LOGNAME ${arg_LOGNAME}-rel
             )
+            list(APPEND config_logs
+                "${CURRENT_BUILDTREES_DIR}/${arg_LOGNAME}-rel-out.log"
+                "${CURRENT_BUILDTREES_DIR}/${arg_LOGNAME}-rel-err.log")
+        endif()
+    endif()
+
+    # Check unused variables
+    set(all_unused_variables)
+    foreach(config_log IN LISTS config_logs)
+        if (NOT EXISTS "${config_log}")
+            continue()
+        endif()
+        file(READ "${config_log}" log_contents)
+        debug_message("Reading configure log ${config_log}...")
+        if(NOT log_contents MATCHES "Manually-specified variables were not used by the project:\n\n((    [^\n]*\n)*)")
+            continue()
         endif()
+        string(STRIP "${CMAKE_MATCH_1}" unused_variables) # remove leading `    ` and trailing `\n`
+        string(REPLACE "\n    " ";" unused_variables "${unused_variables}")
+        debug_message("unused variables: ${unused_variables}")
+
+        foreach(unused_variable IN LISTS unused_variables)
+            if(unused_variable IN_LIST manually_specified_variables)
+                debug_message("manually specified unused variable: ${unused_variable}")
+                list(APPEND all_unused_variables "${unused_variable}")
+            else()
+                debug_message("unused variable (not manually specified): ${unused_variable}")
+            endif()
+        endforeach()
+    endforeach()
+
+    if(DEFINED all_unused_variables)
+        list(REMOVE_DUPLICATES all_unused_variables)
+        list(JOIN all_unused_variables "\n    " all_unused_variables)
+        message(WARNING "The following variables are not used in CMakeLists.txt:
+    ${all_unused_variables}
+Please recheck them and remove the unnecessary options from the `vcpkg_configure_cmake` call.
+If these options should still be passed for whatever reason, please use the `MAYBE_UNUSED_VARIABLES` argument.")
     endif()
 
     set(Z_VCPKG_CMAKE_GENERATOR "${GENERATOR}" PARENT_SCOPE)

scripts/cmake/vcpkg_internal_get_cmake_vars.cmake

@@ -53,6 +53,7 @@ function(vcpkg_internal_get_cmake_vars)
         OPTIONS_RELEASE "-DVCPKG_OUTPUT_FILE:PATH=${CURRENT_BUILDTREES_DIR}/cmake-vars-${TARGET_TRIPLET}-rel.cmake.log"
         PREFER_NINJA
         LOGNAME get-cmake-vars-${TARGET_TRIPLET}
+        Z_VCPKG_IGNORE_UNUSED_VARIABLES
     )
 
     set(_include_string)

versions/v-/vcpkg-cmake.json

@@ -1,5 +1,10 @@
 {
   "versions": [
+    {
+      "git-tree": "6404018e597cf6703e4cf3d46a3a4011d8c93efd",
+      "version-date": "2021-02-28",
+      "port-version": 5
+    },
     {
       "git-tree": "0e8bb94599a00fd9c61fd0ae524c22a067c21420",
       "version-date": "2021-02-28",