Knowledge Base

BUG: You may receive multiple errors when you compile the Standard C++ Library headers with the /Za switch in Visual C++

Article ID: 168934

Article Last Modified on 9/2/2005


APPLIES TO


This article was previously published under Q168934

SYMPTOMS

If you use the /Za switch (Disable Language Extensions) when compiling the Standard C++ Library headers, it causes multiple compiler errors. For example:
   cl /Za /c /GX /Tp"iosfwd"
				
Causes the following compiler errors:
iosfwd(132) : error C2906: C++ language change: to explicitly specialize class template 'char_traits' use the following syntax - template<> struct char_traits<unsigned short> ...

iosfwd(171) : error C2906: C++ language change: to explicitly specialize class template 'char_traits' use the following syntax - template<> struct char_traits<char> ...
Examples of other header files known to cause multiple compiler errors like C2838, C2146, and C2501 are: <utility>, <iterator>, <xstring>, <functional>, and <limits>.

RESOLUTION

Do not use the compiler option /Za (Disable Language Extensions) when compiling the Standard C++ Library headers.

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article.

This problem was corrected in Microsoft Visual C++ .NET.

Keywords: kberrmsg kbtshoot kbbug kbfix kbnoupdate kblangcpp kbcpponly kbcompiler KB168934