CDRIVER-2145 CMake option ENABLE_MAINTAINER_FLAGS

Author: ajdavis

.evergreen/compile-windows.sh

@@ -11,7 +11,7 @@ set -o errexit  # Exit the script with error if any of the commands fail
 
 
 INSTALL_DIR="C:/mongoc"
-CONFIGURE_FLAGS="-DCMAKE_INSTALL_PREFIX=${INSTALL_DIR} -DENABLE_AUTOMATIC_INIT_AND_CLEANUP:BOOL=OFF"
+CONFIGURE_FLAGS="-DCMAKE_INSTALL_PREFIX=${INSTALL_DIR} -DENABLE_AUTOMATIC_INIT_AND_CLEANUP:BOOL=OFF -DENABLE_MAINTAINER_FLAGS=ON"
 BUILD_FLAGS="/m"  # Number of concurrent processes. No value=# of cpus
 CMAKE="/cygdrive/c/cmake/bin/cmake"
 CC=${CC:-"Visual Studio 14 2015 Win64"}

CMakeLists.txt

@@ -1,5 +1,15 @@
 cmake_minimum_required(VERSION 3.1)
 
+set (MESSAGES_ENABLED 1)
+
+function(message)
+   list (GET ARGV 0 MessageType)
+   if (MESSAGES_ENABLED)
+      list (REMOVE_AT ARGV 0)
+      _message (${MessageType} "${ARGV}")
+   endif()
+endfunction()
+
 set (ENABLE_SSL AUTO CACHE STRING
      "Enable TLS connections and SCRAM-SHA-1 authentication.\ Options are
      \"DARWIN\" to use Apple's Secure Transport, \"WINDOWS\" to use Windows
@@ -15,6 +25,7 @@ set (ENABLE_SASL AUTO CACHE STRING
 set(ENABLE_STATIC AUTO CACHE STRING "Build static libmongoc. Set to ON/AUTO/OFF, default AUTO.")
 option(ENABLE_TESTS "Build MongoDB C Driver tests." ON)
 option(ENABLE_EXAMPLES "Build MongoDB C Driver examples." ON)
+option(ENABLE_MAINTAINER_FLAGS "Use strict compiler checks" OFF)
 option(ENABLE_AUTOMATIC_INIT_AND_CLEANUP "Enable automatic init and cleanup (GCC only)" ON)
 option(ENABLE_CRYPTO_SYSTEM_PROFILE "Use system crypto profile (OpenSSL only)" OFF)
 option(ENABLE_TRACING "Turn on verbose debug output" OFF)
@@ -45,6 +56,8 @@ if (NOT ${MONGOC_VERSION} STREQUAL ${MONGOC_RELEASED_VERSION})
    message("Previous release (from VERSION_RELEASED file): ${MONGOC_RELEASED_VERSION}")
 endif()
 
+include(MaintainerFlags)
+
 # The input variable BSON_ROOT_DIR is respected for backwards compatibility,
 # but you should use the standard CMAKE_PREFIX_PATH instead.
 message (STATUS "Searching for libbson CMake packages")
@@ -367,6 +380,8 @@ if (APPLE)
    add_definitions(-Wno-deprecated-declarations)
 endif()
 
+include (MaintainerFlags)
+
 set (SOURCES
    ${SOURCE_DIR}/src/mongoc/mongoc-apm.c
    ${SOURCE_DIR}/src/mongoc/mongoc-array.c

Makefile.am

@@ -35,7 +35,7 @@ include examples/Makefile.am
 endif
 
 # for EXTRA_DIST
-include build/cmake/Makefile.am
+include build/Makefile.am
 
 ACLOCAL_AMFLAGS = -I build/autotools/m4 ${ACLOCAL_FLAGS}
 DISTCHECK_CONFIGURE_FLAGS = --enable-silent-rules --enable-man-pages --enable-html-docs --enable-sasl --enable-ssl --enable-maintainer-flags --enable-debug --with-libbson=bundled --with-snappy=bundled --with-zlib=bundled

build/Makefile.am

@@ -0,0 +1,3 @@
+EXTRA_DIST += build/maintainer-flags.txt
+
+include build/cmake/Makefile.am

build/autotools/MaintainerFlags.m4

@@ -1,29 +1,22 @@
-old_CFLAGS="$CFLAGS"
-CFLAGS="-Werror"
 AS_IF(
    [test "x$enable_maintainer_flags" = "xyes" && test "x$GCC" = "xyes"],
    [
-      AX_CHECK_COMPILE_FLAG([-Wall],                         [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wall"])
-      AX_CHECK_COMPILE_FLAG([-Waggregate-return],            [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Waggregate-return"])
-      AX_CHECK_COMPILE_FLAG([-Wdeclaration-after-statement], [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wdeclaration-after-statement"])
-      AX_CHECK_COMPILE_FLAG([-Wempty-body],                  [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wempty-body"])
-      AX_CHECK_COMPILE_FLAG([-Wformat],                      [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wformat"])
-      AX_CHECK_COMPILE_FLAG([-Wformat-nonliteral],           [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wformat-nonliteral"])
-      AX_CHECK_COMPILE_FLAG([-Wformat-security],             [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wformat-security"])
-      AX_CHECK_COMPILE_FLAG([-Winit-self],                   [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Winit-self"])
-      AX_CHECK_COMPILE_FLAG([-Winline],                      [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Winline"])
-      AX_CHECK_COMPILE_FLAG([-Wmissing-include-dirs],        [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wmissing-include-dirs"])
-      AX_CHECK_COMPILE_FLAG([-Wno-strict-aliasing],          [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wno-strict-aliasing"])
-      AX_CHECK_COMPILE_FLAG([-Wno-uninitialized],            [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wno-uninitialized"])
-      AX_CHECK_COMPILE_FLAG([-Wredundant-decls],             [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wredundant-decls"])
-      AX_CHECK_COMPILE_FLAG([-Wreturn-type],                 [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wreturn-type"])
-      AX_CHECK_COMPILE_FLAG([-Wshadow],                      [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wshadow"])
-      AX_CHECK_COMPILE_FLAG([-Wswitch-default],              [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wswitch-default"])
-      AX_CHECK_COMPILE_FLAG([-Wswitch-enum],                 [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wswitch-enum"])
-      AX_CHECK_COMPILE_FLAG([-Wundef],                       [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wundef"])
-      AX_CHECK_COMPILE_FLAG([-Wuninitialized],               [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wuninitialized"])
-      AX_CHECK_COMPILE_FLAG([-Wexpansion-to-defined],        [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS -Wexpansion-to-defined"])
+    # clang only warns if it doesn't support a warning option, turn it into an
+    # error so we really know if whether it supports it.
+    AX_CHECK_COMPILE_FLAG(
+       "-Werror=unknown-warning-option",
+       [WERROR_UNKNOWN_OPTION="-Werror=unknown-warning-option"],
+       [WERROR_UNKNOWN_OPTION=""])
+
+    # Read maintainer-flags.txt and apply each flag that the compiler supports.
+    m4_foreach([MAINTAINER_FLAG], m4_split(m4_normalize(m4_esyscmd(cat build/maintainer-flags.txt))), [
+        AX_CHECK_COMPILE_FLAG(
+           MAINTAINER_FLAG,
+           [MAINTAINER_CFLAGS="$MAINTAINER_CFLAGS MAINTAINER_FLAG"],
+           [],
+           [$WERROR_UNKNOWN_OPTION])
+    ])
    ]
+
+   AC_SUBST(MAINTAINER_CFLAGS)
 )
-AC_SUBST(MAINTAINER_CFLAGS)
-CFLAGS="$old_CFLAGS"

build/cmake/MaintainerFlags.cmake

@@ -0,0 +1,28 @@
+if (ENABLE_MAINTAINER_FLAGS)
+   include(CheckCCompilerFlag)
+
+   message(STATUS "Detecting available maintainer flags")
+   file (READ "build/maintainer-flags.txt" MAINTAINER_FLAGS)
+
+   # Convert file contents into a CMake list (where each element in the list
+   # is one line of the file)
+   #
+   string (REGEX REPLACE ";" "\\\\;" MAINTAINER_FLAGS "${MAINTAINER_FLAGS}")
+   string (REGEX REPLACE "\n" ";" MAINTAINER_FLAGS "${MAINTAINER_FLAGS}")
+
+   foreach (MAINTAINER_FLAG ${MAINTAINER_FLAGS})
+      # Avoid useless "Performing Test FLAG_OK" message.
+      set (MESSAGES_ENABLED 0)
+      check_c_compiler_flag ("${MAINTAINER_FLAG}" FLAG_OK)
+      set (MESSAGES_ENABLED 1)
+      if (FLAG_OK)
+         message (STATUS "C compiler accepts ${MAINTAINER_FLAG}")
+         set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${MAINTAINER_FLAG}")
+      else ()
+         message (STATUS "C compiler does not accept ${MAINTAINER_FLAG}")
+      endif ()
+      unset (FLAG_OK CACHE)
+   endforeach ()
+
+   message(STATUS "Maintainer flags: ${CMAKE_C_FLAGS}")
+endif ()

build/cmake/Makefile.am

@@ -6,4 +6,5 @@ EXTRA_DIST += \
 	build/cmake/libmongoc-1.0-config-version.cmake.in \
 	build/cmake/libmongoc-static-1.0-config.cmake.in \
 	build/cmake/libmongoc-static-1.0-config-version.cmake.in \
-	build/cmake/LoadVersion.cmake
+	build/cmake/LoadVersion.cmake \
+	build/cmake/MaintainerFlags.cmake

build/maintainer-flags.txt

@@ -0,0 +1,20 @@
+-Wall
+-Waggregate-return
+-Wdeclaration-after-statement
+-Wempty-body
+-Wformat
+-Wformat-nonliteral
+-Wformat-security
+-Winit-self
+-Winline
+-Wmissing-include-dirs
+-Wno-strict-aliasing
+-Wno-uninitialized
+-Wredundant-decls
+-Wreturn-type
+-Wshadow
+-Wswitch-default
+-Wswitch-enum
+-Wundef
+-Wuninitialized
+-Wexpansion-to-defined