问题
Hi I am getting so many syntax errors in the standard microsoft file "iosfwd" & atlconv.h". (I have pasted some errors below):: Really dont understand the reason behind such errors in standard file iosfwd & atlconv.h . Any help is greatly appreciated.
ERRORS in IOSFWD
\program files (x86)\microsoft visual studio 9.0\vc\include\iosfwd(350) : error C2065: '_Size_in_words' : undeclared identifier
3>c:\program files (x86)\microsoft visual studio 9.0\vc\include\iosfwd(350) : error C2065: '_First2' : undeclared identifier
3>c:\program files (x86)\microsoft visual studio 9.0\vc\include\iosfwd(350) : error C2065: '_Count' : undeclared identifier
3>c:\program files (x86)\microsoft visual studio 9.0\vc\include\iosfwd(350) : error C3861: '_CRT_SECURE_WMEMCPY': identifier not found
3>c:\program files (x86)\microsoft visual studio 9.0\vc\include\iosfwd(351) : error C2065: '_First1' : undeclared identifier
3>c:\program files (x86)\microsoft visual studio 9.0\vc\include\iosfwd(358) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
3>c:\program files (x86)\microsoft visual studio 9.0\vc\include\iosfwd(358) : error C2146: syntax error : missing ')' before identifier '_Elem'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\include\iosfwd(358) : error C2059: syntax error : ')'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\include\iosfwd(358) : error C2059: syntax error : ')'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\include\iosfwd(366) : error C2065: '_First1' : undeclared identifier
3>c:\program files (x86)\microsoft visual studio 9.0\vc\include\iosfwd(366) : error C2065: '_Count' : undeclared identifier
ERRORS in atlconv.h::
program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(530) : error C2146: syntax error : missing ')' before identifier 'LPDEVMODEA'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(530) : warning C4229: anachronism used : modifiers on data are ignored
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(530) : error C2495: 'AtlDevModeW2A' : '__declspec(nothrow)' can only be applied to function declarations or definitions
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(530) : error C2059: syntax error : ')'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(535) : error C2065: 'nChars' : undeclared identifier
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(535) : error C2448: '_Ret_opt_z_cap_' : function-style initializer appears to be a function definition
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(535) : error C2143: syntax error : missing ';' before '__stdcall'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(535) : error C2065: 'nChars' : undeclared identifier
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(535) : error C3861: '_Out_z_cap_': identifier not found
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(535) : error C2146: syntax error : missing ')' before identifier 'LPWSTR'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(535) : warning C4229: anachronism used : modifiers on data are ignored
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(535) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(535) : error C2059: syntax error : ')'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(536) : error C2143: syntax error : missing ';' before '{'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(554) : error C2065: 'nChars' : undeclared identifier
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(554) : error C2448: '_Ret_opt_z_cap_' : function-style initializer appears to be a function definition
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(554) : error C2143: syntax error : missing ';' before '__stdcall'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(554) : error C2065: 'nChars' : undeclared identifier
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(554) : error C3861: '_Out_z_cap_': identifier not found
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(554) : error C2146: syntax error : missing ')' before identifier 'LPSTR'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(554) : warning C4229: anachronism used : modifiers on data are ignored
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(554) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(554) : error C2059: syntax error : ')'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(555) : error C2143: syntax error : missing ';' before '{'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(572) : error C2065: 'nChars' : undeclared identifier
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(572) : error C2448: '_Ret_opt_z_cap_' : function-style initializer appears to be a function definition
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(572) : error C2143: syntax error : missing ';' before '__stdcall'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(572) : error C2065: 'nChars' : undeclared identifier
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(572) : error C3861: '_Out_z_cap_': identifier not found
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(572) : error C2146: syntax error : missing ')' before identifier 'LPWSTR'
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(572) : warning C4229: anachronism used : modifiers on data are ignored
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(572) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
3>c:\program files (x86)\microsoft visual studio 9.0\vc\atlmfc\include\atlconv.h(572) : error C2374: 'AtlA2WHelper' : redefinition; multiple initialization
These are just a few errors I have pasted here, as I cant paste every error. But all errors are in these 2 files ONLy (IOSFWD & atlconv.h").
回答1:
You can generally assume that the headers shipping with the compiler are correct, especially, when it is a frequently used one like <iosfwd>. However, compilers sometimes report errors in standard headers when there was an error prior to including them. For example, an unclosed namespace or class, i.e., a missing } can have this effect (this is what I would start looking for in your case) or a missing semicolon after a class definition.
来源：https://stackoverflow.com/questions/12139429/syntax-errors-in-standard-microsoft-files-iosfwd-atlconv-h-while-compiling