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-rw-r--r--Modules/CheckSymbolExists.cmake108
1 files changed, 63 insertions, 45 deletions
diff --git a/Modules/CheckSymbolExists.cmake b/Modules/CheckSymbolExists.cmake
index 0969bc562..6f1afcfda 100644
--- a/Modules/CheckSymbolExists.cmake
+++ b/Modules/CheckSymbolExists.cmake
@@ -1,48 +1,60 @@
-# - Check if a symbol exists as a function, variable, or macro
-# CHECK_SYMBOL_EXISTS(<symbol> <files> <variable>)
-#
-# Check that the <symbol> is available after including given header
-# <files> and store the result in a <variable>. Specify the list
-# of files in one argument as a semicolon-separated list.
-#
-# If the header files define the symbol as a macro it is considered
-# available and assumed to work. If the header files declare the
-# symbol as a function or variable then the symbol must also be
-# available for linking. If the symbol is a type or enum value
-# it will not be recognized (consider using CheckTypeSize or
-# CheckCSourceCompiles).
-# If the check needs to be done in C++, consider using CHECK_CXX_SYMBOL_EXISTS(),
-# which does the same as CHECK_SYMBOL_EXISTS(), but in C++.
-#
-# The following variables may be set before calling this macro to
-# modify the way the check is run:
-#
-# CMAKE_REQUIRED_FLAGS = string of compile command line flags
-# CMAKE_REQUIRED_DEFINITIONS = list of macros to define (-DFOO=bar)
-# CMAKE_REQUIRED_INCLUDES = list of include directories
-# CMAKE_REQUIRED_LIBRARIES = list of libraries to link
+# Distributed under the OSI-approved BSD 3-Clause License. See accompanying
+# file Copyright.txt or https://cmake.org/licensing for details.
-#=============================================================================
-# Copyright 2003-2011 Kitware, Inc.
-#
-# Distributed under the OSI-approved BSD License (the "License");
-# see accompanying file Copyright.txt for details.
-#
-# This software is distributed WITHOUT ANY WARRANTY; without even the
-# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
-# See the License for more information.
-#=============================================================================
-# (To distribute this file outside of CMake, substitute the full
-# License text for the above reference.)
+#[=======================================================================[.rst:
+CheckSymbolExists
+-----------------
+Provides a macro to check if a symbol exists as a function, variable,
+or macro in ``C``.
+.. command:: check_symbol_exists
+
+ ::
+
+ check_symbol_exists(<symbol> <files> <variable>)
+
+ Check that the ``<symbol>`` is available after including given header
+ ``<files>`` and store the result in a ``<variable>``. Specify the list
+ of files in one argument as a semicolon-separated list.
+ ``<variable>`` will be created as an internal cache variable.
+
+If the header files define the symbol as a macro it is considered
+available and assumed to work. If the header files declare the symbol
+as a function or variable then the symbol must also be available for
+linking (so intrinsics may not be detected).
+If the symbol is a type, enum value, or intrinsic it will not be recognized
+(consider using :module:`CheckTypeSize` or :module:`CheckCSourceCompiles`).
+If the check needs to be done in C++, consider using
+:module:`CheckCXXSymbolExists` instead.
+
+The following variables may be set before calling this macro to modify
+the way the check is run:
+
+``CMAKE_REQUIRED_FLAGS``
+ string of compile command line flags
+``CMAKE_REQUIRED_DEFINITIONS``
+ list of macros to define (-DFOO=bar)
+``CMAKE_REQUIRED_INCLUDES``
+ list of include directories
+``CMAKE_REQUIRED_LIBRARIES``
+ list of libraries to link
+``CMAKE_REQUIRED_QUIET``
+ execute quietly without messages
+#]=======================================================================]
macro(CHECK_SYMBOL_EXISTS SYMBOL FILES VARIABLE)
- _CHECK_SYMBOL_EXISTS("${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/CheckSymbolExists.c" "${SYMBOL}" "${FILES}" "${VARIABLE}" )
+ if(CMAKE_C_COMPILER_LOADED)
+ _CHECK_SYMBOL_EXISTS("${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/CheckSymbolExists.c" "${SYMBOL}" "${FILES}" "${VARIABLE}" )
+ elseif(CMAKE_CXX_COMPILER_LOADED)
+ _CHECK_SYMBOL_EXISTS("${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp/CheckSymbolExists.cxx" "${SYMBOL}" "${FILES}" "${VARIABLE}" )
+ else()
+ message(FATAL_ERROR "CHECK_SYMBOL_EXISTS needs either C or CXX language enabled")
+ endif()
endmacro()
macro(_CHECK_SYMBOL_EXISTS SOURCEFILE SYMBOL FILES VARIABLE)
- if("${VARIABLE}" MATCHES "^${VARIABLE}$")
+ if(NOT DEFINED "${VARIABLE}" OR "x${${VARIABLE}}" STREQUAL "x${VARIABLE}")
set(CMAKE_CONFIGURABLE_FILE_CONTENT "/* */\n")
set(MACRO_CHECK_SYMBOL_EXISTS_FLAGS ${CMAKE_REQUIRED_FLAGS})
if(CMAKE_REQUIRED_LIBRARIES)
@@ -58,16 +70,18 @@ macro(_CHECK_SYMBOL_EXISTS SOURCEFILE SYMBOL FILES VARIABLE)
set(CMAKE_SYMBOL_EXISTS_INCLUDES)
endif()
foreach(FILE ${FILES})
- set(CMAKE_CONFIGURABLE_FILE_CONTENT
- "${CMAKE_CONFIGURABLE_FILE_CONTENT}#include <${FILE}>\n")
+ string(APPEND CMAKE_CONFIGURABLE_FILE_CONTENT
+ "#include <${FILE}>\n")
endforeach()
- set(CMAKE_CONFIGURABLE_FILE_CONTENT
- "${CMAKE_CONFIGURABLE_FILE_CONTENT}\nint main(int argc, char** argv)\n{\n (void)argv;\n#ifndef ${SYMBOL}\n return ((int*)(&${SYMBOL}))[argc];\n#else\n (void)argc;\n return 0;\n#endif\n}\n")
+ string(APPEND CMAKE_CONFIGURABLE_FILE_CONTENT
+ "\nint main(int argc, char** argv)\n{\n (void)argv;\n#ifndef ${SYMBOL}\n return ((int*)(&${SYMBOL}))[argc];\n#else\n (void)argc;\n return 0;\n#endif\n}\n")
configure_file("${CMAKE_ROOT}/Modules/CMakeConfigurableFile.in"
- "${SOURCEFILE}" @ONLY IMMEDIATE)
+ "${SOURCEFILE}" @ONLY)
- message(STATUS "Looking for ${SYMBOL}")
+ if(NOT CMAKE_REQUIRED_QUIET)
+ message(STATUS "Looking for ${SYMBOL}")
+ endif()
try_compile(${VARIABLE}
${CMAKE_BINARY_DIR}
"${SOURCEFILE}"
@@ -78,7 +92,9 @@ macro(_CHECK_SYMBOL_EXISTS SOURCEFILE SYMBOL FILES VARIABLE)
"${CMAKE_SYMBOL_EXISTS_INCLUDES}"
OUTPUT_VARIABLE OUTPUT)
if(${VARIABLE})
- message(STATUS "Looking for ${SYMBOL} - found")
+ if(NOT CMAKE_REQUIRED_QUIET)
+ message(STATUS "Looking for ${SYMBOL} - found")
+ endif()
set(${VARIABLE} 1 CACHE INTERNAL "Have symbol ${SYMBOL}")
file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
"Determining if the ${SYMBOL} "
@@ -86,7 +102,9 @@ macro(_CHECK_SYMBOL_EXISTS SOURCEFILE SYMBOL FILES VARIABLE)
"${OUTPUT}\nFile ${SOURCEFILE}:\n"
"${CMAKE_CONFIGURABLE_FILE_CONTENT}\n")
else()
- message(STATUS "Looking for ${SYMBOL} - not found")
+ if(NOT CMAKE_REQUIRED_QUIET)
+ message(STATUS "Looking for ${SYMBOL} - not found")
+ endif()
set(${VARIABLE} "" CACHE INTERNAL "Have symbol ${SYMBOL}")
file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
"Determining if the ${SYMBOL} "