curl/CMake/CurlSymbolHiding.cmake
Tobias Hieta fd5f35ef0b
cmake: don't pass -fvisibility=hidden to clang-cl on Windows
When using clang-cl on windows -fvisibility=hidden is not an known
argument. Instead it behaves exactly like MSVC in this case. So let's
make sure we take that path.

In CMake clang-cl sets both CMAKE_C_COMPILER_ID=clang and MSVC get's
defined since clang-cl is basically a MSVC emulator. So guarding like we
do in this patch seems logical.

Reviewed-by: Jakub Zakrzewski
Closes #6194
2020-11-10 23:40:33 +01:00

77 lines
3.3 KiB
CMake

#***************************************************************************
# _ _ ____ _
# Project ___| | | | _ \| |
# / __| | | | |_) | |
# | (__| |_| | _ <| |___
# \___|\___/|_| \_\_____|
#
# Copyright (C) 1998 - 2020, Daniel Stenberg, <daniel@haxx.se>, et al.
#
# This software is licensed as described in the file COPYING, which
# you should have received as part of this distribution. The terms
# are also available at https://curl.se/docs/copyright.html.
#
# You may opt to use, copy, modify, merge, publish, distribute and/or sell
# copies of the Software, and permit persons to whom the Software is
# furnished to do so, under the terms of the COPYING file.
#
# This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
# KIND, either express or implied.
#
###########################################################################
include(CheckCSourceCompiles)
option(CURL_HIDDEN_SYMBOLS "Set to ON to hide libcurl internal symbols (=hide all symbols that aren't officially external)." ON)
mark_as_advanced(CURL_HIDDEN_SYMBOLS)
if(CURL_HIDDEN_SYMBOLS)
set(SUPPORTS_SYMBOL_HIDING FALSE)
if(CMAKE_C_COMPILER_ID MATCHES "Clang" AND NOT MSVC)
set(SUPPORTS_SYMBOL_HIDING TRUE)
set(_SYMBOL_EXTERN "__attribute__ ((__visibility__ (\"default\")))")
set(_CFLAG_SYMBOLS_HIDE "-fvisibility=hidden")
elseif(CMAKE_COMPILER_IS_GNUCC)
if(NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 3.4)
# note: this is considered buggy prior to 4.0 but the autotools don't care, so let's ignore that fact
set(SUPPORTS_SYMBOL_HIDING TRUE)
set(_SYMBOL_EXTERN "__attribute__ ((__visibility__ (\"default\")))")
set(_CFLAG_SYMBOLS_HIDE "-fvisibility=hidden")
endif()
elseif(CMAKE_C_COMPILER_ID MATCHES "SunPro" AND NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 8.0)
set(SUPPORTS_SYMBOL_HIDING TRUE)
set(_SYMBOL_EXTERN "__global")
set(_CFLAG_SYMBOLS_HIDE "-xldscope=hidden")
elseif(CMAKE_C_COMPILER_ID MATCHES "Intel" AND NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 9.0)
# note: this should probably just check for version 9.1.045 but I'm not 100% sure
# so let's do it the same way autotools do.
set(SUPPORTS_SYMBOL_HIDING TRUE)
set(_SYMBOL_EXTERN "__attribute__ ((__visibility__ (\"default\")))")
set(_CFLAG_SYMBOLS_HIDE "-fvisibility=hidden")
check_c_source_compiles("#include <stdio.h>
int main (void) { printf(\"icc fvisibility bug test\"); return 0; }" _no_bug)
if(NOT _no_bug)
set(SUPPORTS_SYMBOL_HIDING FALSE)
set(_SYMBOL_EXTERN "")
set(_CFLAG_SYMBOLS_HIDE "")
endif()
elseif(MSVC)
set(SUPPORTS_SYMBOL_HIDING TRUE)
endif()
set(HIDES_CURL_PRIVATE_SYMBOLS ${SUPPORTS_SYMBOL_HIDING})
elseif(MSVC)
if(NOT CMAKE_VERSION VERSION_LESS 3.7)
set(CMAKE_WINDOWS_EXPORT_ALL_SYMBOLS TRUE) #present since 3.4.3 but broken
set(HIDES_CURL_PRIVATE_SYMBOLS FALSE)
else()
message(WARNING "Hiding private symbols regardless CURL_HIDDEN_SYMBOLS being disabled.")
set(HIDES_CURL_PRIVATE_SYMBOLS TRUE)
endif()
else()
set(HIDES_CURL_PRIVATE_SYMBOLS FALSE)
endif()
set(CURL_CFLAG_SYMBOLS_HIDE ${_CFLAG_SYMBOLS_HIDE})
set(CURL_EXTERN_SYMBOL ${_SYMBOL_EXTERN})