1#*************************************************************************** 2# _ _ ____ _ 3# Project ___| | | | _ \| | 4# / __| | | | |_) | | 5# | (__| |_| | _ <| |___ 6# \___|\___/|_| \_\_____| 7# 8# Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. 9# 10# This software is licensed as described in the file COPYING, which 11# you should have received as part of this distribution. The terms 12# are also available at https://curl.se/docs/copyright.html. 13# 14# You may opt to use, copy, modify, merge, publish, distribute and/or sell 15# copies of the Software, and permit persons to whom the Software is 16# furnished to do so, under the terms of the COPYING file. 17# 18# This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY 19# KIND, either express or implied. 20# 21# SPDX-License-Identifier: curl 22# 23########################################################################### 24include(CheckCSourceCompiles) 25 26option(CURL_HIDDEN_SYMBOLS "Set to ON to hide libcurl internal symbols (=hide all symbols that aren't officially external)." ON) 27mark_as_advanced(CURL_HIDDEN_SYMBOLS) 28 29if(CURL_HIDDEN_SYMBOLS) 30 set(SUPPORTS_SYMBOL_HIDING FALSE) 31 32 if(CMAKE_C_COMPILER_ID MATCHES "Clang" AND NOT MSVC) 33 set(SUPPORTS_SYMBOL_HIDING TRUE) 34 set(_SYMBOL_EXTERN "__attribute__ ((__visibility__ (\"default\")))") 35 set(_CFLAG_SYMBOLS_HIDE "-fvisibility=hidden") 36 elseif(CMAKE_COMPILER_IS_GNUCC) 37 if(NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 3.4) 38 # note: this is considered buggy prior to 4.0 but the autotools don't care, so let's ignore that fact 39 set(SUPPORTS_SYMBOL_HIDING TRUE) 40 set(_SYMBOL_EXTERN "__attribute__ ((__visibility__ (\"default\")))") 41 set(_CFLAG_SYMBOLS_HIDE "-fvisibility=hidden") 42 endif() 43 elseif(CMAKE_C_COMPILER_ID MATCHES "SunPro" AND NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 8.0) 44 set(SUPPORTS_SYMBOL_HIDING TRUE) 45 set(_SYMBOL_EXTERN "__global") 46 set(_CFLAG_SYMBOLS_HIDE "-xldscope=hidden") 47 elseif(CMAKE_C_COMPILER_ID MATCHES "Intel" AND NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 9.0) 48 # note: this should probably just check for version 9.1.045 but I'm not 100% sure 49 # so let's do it the same way autotools do. 50 set(SUPPORTS_SYMBOL_HIDING TRUE) 51 set(_SYMBOL_EXTERN "__attribute__ ((__visibility__ (\"default\")))") 52 set(_CFLAG_SYMBOLS_HIDE "-fvisibility=hidden") 53 check_c_source_compiles("#include <stdio.h> 54 int main (void) { printf(\"icc fvisibility bug test\"); return 0; }" _no_bug) 55 if(NOT _no_bug) 56 set(SUPPORTS_SYMBOL_HIDING FALSE) 57 set(_SYMBOL_EXTERN "") 58 set(_CFLAG_SYMBOLS_HIDE "") 59 endif() 60 elseif(MSVC) 61 set(SUPPORTS_SYMBOL_HIDING TRUE) 62 endif() 63 64 set(HIDES_CURL_PRIVATE_SYMBOLS ${SUPPORTS_SYMBOL_HIDING}) 65elseif(MSVC) 66 if(NOT CMAKE_VERSION VERSION_LESS 3.7) 67 set(CMAKE_WINDOWS_EXPORT_ALL_SYMBOLS TRUE) #present since 3.4.3 but broken 68 set(HIDES_CURL_PRIVATE_SYMBOLS FALSE) 69 else() 70 message(WARNING "Hiding private symbols regardless CURL_HIDDEN_SYMBOLS being disabled.") 71 set(HIDES_CURL_PRIVATE_SYMBOLS TRUE) 72 endif() 73else() 74 set(HIDES_CURL_PRIVATE_SYMBOLS FALSE) 75endif() 76 77set(CURL_CFLAG_SYMBOLS_HIDE ${_CFLAG_SYMBOLS_HIDE}) 78set(CURL_EXTERN_SYMBOL ${_SYMBOL_EXTERN}) 79