详细请见http://support.microsoft.com/default.aspx?scid=kb;en-us;167355
另附上VC中默认关闭的warning:
The compiler includes warnings that are off by default. If a warning is off by default, most users would not want to see such warnings for their code. However, some users would be interested to see such output from the compiler.
A warning that is off by default can be enabled in one of several ways:
#pragma warning(default : warning_number) The warning is enabled at its default level. Documentation for the warning contains the default level of the warning. #pragma warning(warning_level : warning_number) The warning is enabled at the specified level (warning_level). /Wall This compiler option enables all warnings that are off by default. The following warnings are off by default:
C4056 C4061 C4062 C4191 C4217 C4242 C4254 C4255 C4263 C4264 C4265 C4287 C4289 C4296 C4302 C4339 C4347 C4514 C4529 C4545 C4546 C4547 C4548 C4549 C4536 C4555 C4557 C4619 C4623 C4625 C4626 C4628 C4640 C4668 C4682 C4686 C4710 C4786 C4793 C4820 C4905 C4906 C4917 C4928 C4931 C4946
