CMake/CurlSymbolHiding.cmake

   1 include(CheckCSourceCompiles)
   2
   3 option(CURL_HIDDEN_SYMBOLS "Set to ON to hide libcurl internal symbols (=hide all symbols that aren't officially external)." ON)
   4 mark_as_advanced(CURL_HIDDEN_SYMBOLS)
   5
   6 if(CURL_HIDDEN_SYMBOLS)
   7     set(SUPPORTS_SYMBOL_HIDING FALSE)
   8
   9     if(CMAKE_C_COMPILER_ID MATCHES "Clang")
  10         set(SUPPORTS_SYMBOL_HIDING TRUE)
  11         set(_SYMBOL_EXTERN "__attribute__ ((__visibility__ (\"default\")))")
  12         set(_CFLAG_SYMBOLS_HIDE "-fvisibility=hidden")
  13     elseif(CMAKE_COMPILER_IS_GNUCC)
  14         if(NOT CMAKE_VERSION VERSION_LESS 2.8.10)
  15             set(GCC_VERSION ${CMAKE_C_COMPILER_VERSION})
  16         else()
  17             execute_process(COMMAND ${CMAKE_C_COMPILER} -dumpversion
  18                             OUTPUT_VARIABLE GCC_VERSION)
  19         endif()
  20         if(NOT GCC_VERSION VERSION_LESS 3.4)
  21             # note: this is considered buggy prior to 4.0 but the autotools don't care, so let's ignore that fact
  22             set(SUPPORTS_SYMBOL_HIDING TRUE)
  23             set(_SYMBOL_EXTERN "__attribute__ ((__visibility__ (\"default\")))")
  24             set(_CFLAG_SYMBOLS_HIDE "-fvisibility=hidden")
  25         endif()
  26     elseif(CMAKE_C_COMPILER_ID MATCHES "SunPro" AND NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 8.0)
  27         set(SUPPORTS_SYMBOL_HIDING TRUE)
  28         set(_SYMBOL_EXTERN "__global")
  29         set(_CFLAG_SYMBOLS_HIDE "-xldscope=hidden")
  30     elseif(CMAKE_C_COMPILER_ID MATCHES "Intel" AND NOT CMAKE_C_COMPILER_VERSION VERSION_LESS 9.0)
  31         # note: this should probably just check for version 9.1.045 but I'm not 100% sure
  32         #       so let's to it the same way autotools do.
  33         set(SUPPORTS_SYMBOL_HIDING TRUE)
  34         set(_SYMBOL_EXTERN "__attribute__ ((__visibility__ (\"default\")))")
  35         set(_CFLAG_SYMBOLS_HIDE "-fvisibility=hidden")
  36         check_c_source_compiles("#include <stdio.h>
  37             int main (void) { printf(\"icc fvisibility bug test\"); return 0; }" _no_bug)
  38         if(NOT _no_bug)
  39             set(SUPPORTS_SYMBOL_HIDING FALSE)
  40             set(_SYMBOL_EXTERN "")
  41             set(_CFLAG_SYMBOLS_HIDE "")
  42         endif()
  43     elseif(MSVC)
  44         set(SUPPORTS_SYMBOL_HIDING TRUE)
  45     endif()
  46
  47     set(HIDES_CURL_PRIVATE_SYMBOLS ${SUPPORTS_SYMBOL_HIDING})
  48 elseif(MSVC)
  49     if(NOT CMAKE_VERSION VERSION_LESS 3.7)
  50         set(CMAKE_WINDOWS_EXPORT_ALL_SYMBOLS TRUE) #present since 3.4.3 but broken
  51         set(HIDES_CURL_PRIVATE_SYMBOLS FALSE)
  52     else()
  53         message(WARNING "Hiding private symbols regardless CURL_HIDDEN_SYMBOLS being disabled.")
  54         set(HIDES_CURL_PRIVATE_SYMBOLS TRUE)
  55     endif()
  56 elseif()
  57     set(HIDES_CURL_PRIVATE_SYMBOLS FALSE)
  58 endif()
  59
  60 set(CURL_CFLAG_SYMBOLS_HIDE ${_CFLAG_SYMBOLS_HIDE})
  61 set(CURL_EXTERN_SYMBOL ${_SYMBOL_EXTERN})