blob: 0d44d565541d08413aaf2f46eed7ef3baa3fb98d (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
|
# Distributed under the OSI-approved BSD 3-Clause License. See accompanying
# file Copyright.txt or https://cmake.org/licensing for details.
#[=======================================================================[.rst:
CheckSymbolExists
-----------------
Provides a macro to check if a symbol exists as a function, variable,
or macro in ``C``.
.. command:: check_symbol_exists
.. code-block:: cmake
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:`CheckSourceCompiles`).
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``
a :ref:`;-list <CMake Language Lists>` of macros to define (-DFOO=bar).
``CMAKE_REQUIRED_INCLUDES``
a :ref:`;-list <CMake Language Lists>` of header search paths to pass to
the compiler.
``CMAKE_REQUIRED_LINK_OPTIONS``
.. versionadded:: 3.14
a :ref:`;-list <CMake Language Lists>` of options to add to the link command.
``CMAKE_REQUIRED_LIBRARIES``
a :ref:`;-list <CMake Language Lists>` of libraries to add to the link
command. See policy :policy:`CMP0075`.
``CMAKE_REQUIRED_QUIET``
.. versionadded:: 3.1
execute quietly without messages.
For example:
.. code-block:: cmake
include(CheckSymbolExists)
# Check for macro SEEK_SET
check_symbol_exists(SEEK_SET "stdio.h" HAVE_SEEK_SET)
# Check for function fopen
check_symbol_exists(fopen "stdio.h" HAVE_FOPEN)
#]=======================================================================]
include_guard(GLOBAL)
cmake_policy(PUSH)
cmake_policy(SET CMP0054 NEW) # if() quoted variables not dereferenced
macro(CHECK_SYMBOL_EXISTS SYMBOL FILES VARIABLE)
if(CMAKE_C_COMPILER_LOADED)
__CHECK_SYMBOL_EXISTS_FILTER_FLAGS(C)
__CHECK_SYMBOL_EXISTS_IMPL(CheckSymbolExists.c "${SYMBOL}" "${FILES}" "${VARIABLE}" )
__CHECK_SYMBOL_EXISTS_RESTORE_FLAGS(C)
elseif(CMAKE_CXX_COMPILER_LOADED)
__CHECK_SYMBOL_EXISTS_FILTER_FLAGS(CXX)
__CHECK_SYMBOL_EXISTS_IMPL(CheckSymbolExists.cxx "${SYMBOL}" "${FILES}" "${VARIABLE}" )
__CHECK_SYMBOL_EXISTS_RESTORE_FLAGS(CXX)
else()
message(FATAL_ERROR "CHECK_SYMBOL_EXISTS needs either C or CXX language enabled")
endif()
endmacro()
macro(__CHECK_SYMBOL_EXISTS_FILTER_FLAGS LANG)
set(__CMAKE_${LANG}_FLAGS_SAVED "${CMAKE_${LANG}_FLAGS}")
string(REGEX REPLACE "(^| )-Werror([= ][^ ]*)?( |$)" " " CMAKE_${LANG}_FLAGS "${CMAKE_${LANG}_FLAGS}")
string(REGEX REPLACE "(^| )-pedantic-errors( |$)" " " CMAKE_${LANG}_FLAGS "${CMAKE_${LANG}_FLAGS}")
endmacro()
macro(__CHECK_SYMBOL_EXISTS_RESTORE_FLAGS LANG)
set(CMAKE_${LANG}_FLAGS "${__CMAKE_${LANG}_FLAGS_SAVED}")
unset(__CMAKE_${LANG}_FLAGS_SAVED)
endmacro()
macro(__CHECK_SYMBOL_EXISTS_IMPL SOURCEFILE SYMBOL FILES VARIABLE)
if(NOT DEFINED "${VARIABLE}" OR "x${${VARIABLE}}" STREQUAL "x${VARIABLE}")
set(_CSE_SOURCE "/* */\n")
set(MACRO_CHECK_SYMBOL_EXISTS_FLAGS ${CMAKE_REQUIRED_FLAGS})
if(CMAKE_REQUIRED_LINK_OPTIONS)
set(CHECK_SYMBOL_EXISTS_LINK_OPTIONS
LINK_OPTIONS ${CMAKE_REQUIRED_LINK_OPTIONS})
else()
set(CHECK_SYMBOL_EXISTS_LINK_OPTIONS)
endif()
if(CMAKE_REQUIRED_LIBRARIES)
set(CHECK_SYMBOL_EXISTS_LIBS
LINK_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES})
else()
set(CHECK_SYMBOL_EXISTS_LIBS)
endif()
if(CMAKE_REQUIRED_INCLUDES)
set(CMAKE_SYMBOL_EXISTS_INCLUDES
"-DINCLUDE_DIRECTORIES:STRING=${CMAKE_REQUIRED_INCLUDES}")
else()
set(CMAKE_SYMBOL_EXISTS_INCLUDES)
endif()
foreach(FILE ${FILES})
string(APPEND _CSE_SOURCE
"#include <${FILE}>\n")
endforeach()
string(APPEND _CSE_SOURCE "
int main(int argc, char** argv)
{
(void)argv;")
set(_CSE_CHECK_NON_MACRO "return ((int*)(&${SYMBOL}))[argc];")
if("${SYMBOL}" MATCHES "^[a-zA-Z_][a-zA-Z0-9_]*$")
# The SYMBOL has a legal macro name. Test whether it exists as a macro.
string(APPEND _CSE_SOURCE "
#ifndef ${SYMBOL}
${_CSE_CHECK_NON_MACRO}
#else
(void)argc;
return 0;
#endif")
else()
# The SYMBOL cannot be a macro (e.g., a template function).
string(APPEND _CSE_SOURCE "
${_CSE_CHECK_NON_MACRO}")
endif()
string(APPEND _CSE_SOURCE "
}")
unset(_CSE_CHECK_NON_MACRO)
if(NOT CMAKE_REQUIRED_QUIET)
message(CHECK_START "Looking for ${SYMBOL}")
endif()
try_compile(${VARIABLE}
SOURCE_FROM_VAR "${SOURCEFILE}" _CSE_SOURCE
COMPILE_DEFINITIONS ${CMAKE_REQUIRED_DEFINITIONS}
${CHECK_SYMBOL_EXISTS_LINK_OPTIONS}
${CHECK_SYMBOL_EXISTS_LIBS}
CMAKE_FLAGS
-DCOMPILE_DEFINITIONS:STRING=${MACRO_CHECK_SYMBOL_EXISTS_FLAGS}
"${CMAKE_SYMBOL_EXISTS_INCLUDES}"
OUTPUT_VARIABLE OUTPUT)
if(${VARIABLE})
if(NOT CMAKE_REQUIRED_QUIET)
message(CHECK_PASS "found")
endif()
set(${VARIABLE} 1 CACHE INTERNAL "Have symbol ${SYMBOL}")
file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
"Determining if the ${SYMBOL} "
"exist passed with the following output:\n"
"${OUTPUT}\nFile ${SOURCEFILE}:\n"
"${_CSE_SOURCE}\n")
else()
if(NOT CMAKE_REQUIRED_QUIET)
message(CHECK_FAIL "not found")
endif()
set(${VARIABLE} "" CACHE INTERNAL "Have symbol ${SYMBOL}")
file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
"Determining if the ${SYMBOL} "
"exist failed with the following output:\n"
"${OUTPUT}\nFile ${SOURCEFILE}:\n"
"${_CSE_SOURCE}\n")
endif()
unset(_CSE_SOURCE)
endif()
endmacro()
cmake_policy(POP)
|
