0ct0pu5/wesnoth
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Check floating point mode at startup

Browse source 
this detects wrong floating point modes which cause OOS
(http://gna.org/bugs/?24223) or even casue lua to crash, because lua relies
on IEEE 754 double precision and also on IEEE 754 nearest rounding.
This commit is contained in:
gfgtdf 2015-12-28 14:24:03 +01:00
parent 3955308e7e
commit 4924082687
1 changed files with 38 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

38
src/wesnoth.cpp
View file

@ -514,6 +514,41 @@ static void handle_lua_script_args(game_launcher * game, commandline_options & /
} }
} }
#ifdef _WIN32
static void check_fpu()
{
uint32_t f_control;
if(_controlfp_s(&f_control, 0, 0) == 0) {
uint32_t unused;
uint32_t rounding_mode = f_control & _MCW_RC;
uint32_t precision_mode = f_control & _MCW_PC;
if(rounding_mode != _RC_NEAR) {
std::cerr << "Floating point rounding mode is currently '" <<
((rounding_mode == _RC_CHOP) ? "chop" :
(rounding_mode == _RC_UP) ? "up" :
(rounding_mode == _RC_DOWN) ? "down" :
(rounding_mode == _RC_NEAR) ? "near" :
"unknown") << "' setting to 'near'\n";
if(_controlfp_s(&unused, _RC_NEAR, _MCW_RC)) {
std::cerr << "failed to set floating point rounding type to 'near'\n";
}
}
if(precision_mode != _PC_53) {
std::cerr << "Floating point precision mode is currently '" <<
((precision_mode == _PC_53) ? "double" :
(precision_mode == _PC_24) ? "single" :
(precision_mode == _PC_64 ) ? "double extended" :
"unknown") << "' setting to 'double'\n";
if(_controlfp_s(&unused, _PC_53, _MCW_PC)) {
std::cerr << "failed to set floating point precision type to 'double'\n";
}
}
}
else {
std::cerr << "_controlfp_s failed.\n";
}
}
#endif
/** /**
* Setups the game environment and enters * Setups the game environment and enters
* the titlescreen or game loops. * the titlescreen or game loops.
@ -573,6 +608,9 @@ static int do_gameloop(const std::vector<std::string>& args)
} }
} }
#if defined(_WIN32)
check_fpu();
#endif
const cursor::manager cursor_manager; const cursor::manager cursor_manager;
cursor::set(cursor::WAIT); cursor::set(cursor::WAIT);