I was playing with VS2019 and found out that it works with clang. So I installed clang and I've been having some issues with it working with VS2019. However, this issue is only based on the compiler. Seems that if I were to compile with the command line:
C:\Program Files\LLVM\msbuild-bin\cl.exe /std:c++17 source.cpp
Where source.cpp contains:
#include <tuple>
#include <iostream>
void fn(int x)
{
std::cout << x << std::endl;
}
int main()
{
std::tuple<int> x(1);
apply(fn, x);
return 0;
}
It barfs up:
clang-cl.exe: warning: argument unused during compilation: '/std:c++17' [-Wunused-command-line-argument]
In file included from source.cpp:1:
In file included from C:\Program Files (x86)\Microsoft Visual Studio\2019\Preview\VC\Tools\MSVC\14.20.27508\include\tuple:6:
In file included from C:\Program Files (x86)\Microsoft Visual Studio\2019\Preview\VC\Tools\MSVC\14.20.27508\include\new:6:
In file included from C:\Program Files (x86)\Microsoft Visual Studio\2019\Preview\VC\Tools\MSVC\14.20.27508\include\exception:7:
In file included from C:\Program Files (x86)\Microsoft Visual Studio\2019\Preview\VC\Tools\MSVC\14.20.27508\include\yvals.h:7:
C:\Program Files (x86)\Microsoft Visual Studio\2019\Preview\VC\Tools\MSVC\14.20.27508\include\yvals_core.h(334,2): error: STL1000: Unexpected compiler version, expected Clang 7 or newer.
#error STL1000: Unexpected compiler version, expected Clang 7 or newer.
^
source.cpp(12,3): error: use of undeclared identifier 'apply'
apply(fn, x);
^
2 errors generated.
However, if I use:
"C:\Program Files\LLVM\bin\clang-cl" /std:c++17 source.cpp
All is well.
Thing is, VS2019 is using the former compiler executable. How do I get it to use the latter?
The only thing I did to change the builder was to go and change this item:
Is there anything else I am to be changing?
Related
I have been looking at the example code from Microsoft for using WinHTTP over COM, see: https://learn.microsoft.com/en-us/windows/win32/winhttp/iwinhttprequest-open
The first few lines of the code are as follows:
#include <windows.h>
#include <stdio.h>
#include <objbase.h>
#include "httprequest.h"
#pragma comment(lib, "ole32.lib")
#pragma comment(lib, "oleaut32.lib")
// IID for IWinHttpRequest.
const IID IID_IWinHttpRequest =
{
0x06f29373,
0x5c5a,
0x4b54,
{0xb0, 0x25, 0x6e, 0xf1, 0xbf, 0x8a, 0xbf, 0x0e}
};
int main()
{
// Variable for return value
HRESULT hr;
// Initialize COM
hr = CoInitialize( NULL );
IWinHttpRequest * pIWinHttpRequest = NULL;
I am confused with the correct way to #include the IWinHttpRequest type. I think it comes from the httprequest.h file which is not a system include file.
Also, I guess httprequest.h is the result of compiling httprequest.idl. Am I supposed to manually compile httprequest.idl, or as this is part of the Windows SDK is there a better way to access this type?
There are just missing instructions on how to get the httprequest.h file. The Windows SDK only has the .idl file. This is somehow unusual, many Windows APIs have the .idl and the .h, some only have .h, some only have .idl ... But you can create the .h from the .idl:
open Visual Studio's developer command prompt
type 'midl httprequest.idl /out [your project path]'
This is a sample output:
**********************************************************************
** Visual Studio 2019 Developer Command Prompt v16.5.1
** Copyright (c) 2019 Microsoft Corporation
**********************************************************************
C:\Program Files (x86)\Microsoft Visual Studio\2019\Professional>midl httprequest.idl /out D:\MyPath\MyAppDir
Microsoft (R) 32b/64b MIDL Compiler Version 8.01.0622
Copyright (c) Microsoft Corporation. All rights reserved.
Processing C:\Program Files (x86)\Windows Kits\10\include\10.0.18362.0\um\httprequest.idl
httprequest.idl
Processing C:\Program Files (x86)\Windows Kits\10\include\10.0.18362.0\um\oaidl.idl
oaidl.idl
Processing C:\Program Files (x86)\Windows Kits\10\include\10.0.18362.0\um\objidl.idl
objidl.idl
Processing C:\Program Files (x86)\Windows Kits\10\include\10.0.18362.0\um\unknwn.idl
unknwn.idl
Processing C:\Program Files (x86)\Windows Kits\10\include\10.0.18362.0\shared\wtypes.idl
wtypes.idl
Processing C:\Program Files (x86)\Windows Kits\10\include\10.0.18362.0\shared\wtypesbase.idl
wtypesbase.idl
Processing C:\Program Files (x86)\Windows Kits\10\include\10.0.18362.0\shared\basetsd.h
basetsd.h
Processing C:\Program Files (x86)\Windows Kits\10\include\10.0.18362.0\shared\guiddef.h
guiddef.h
Processing C:\Program Files (x86)\Windows Kits\10\include\10.0.18362.0\um\oaidl.acf
oaidl.acf
It will create 3 files: httprequest.h, httprequest.tlb and httprequest_i.c in your project directory.
Now you should be able to compile the sample code. Note if you include the httprequest_i.c file, you can even remove the manual declaration of IID_IWinHttpRequest in the sample.
Well, knowing absolutely nothing about this beforehand, I looked up the interface you gave, IWinHttpRequest. I went to the registry and searched for it in HKCR\Interface, found the typelib for the interface in the registry. The typelib is HKEY_CLASSES_ROOT\TypeLib\{662901FC-6951-4854-9EB2-D9A2570F2B2E}. From the typelib, looked up HKEY_CLASSES_ROOT\TypeLib\{662901FC-6951-4854-9EB2-D9A2570F2B2E}\5.1\0\win32. The win32 entry shows where the location of the typelib on disk is: %SystemRoot%\system32\winhttpcom.dll
Since the %SystemRoot%\system32 directly is always in the path, you can use the typelib simmply like this:
#import "winhttpcom.dll"
Behind the scenes, the Visual C++ compiler will create files named winhttpcom.tlh and winhttpcom.tli. You can ignore those files. The compiler just automatically includes and links with those files.
It will declare COM smart pointers in the .tlh file:
_COM_SMARTPTR_TYPEDEF(IWinHttpRequest, __uuidof(IWinHttpRequest));
_COM_SMARTPTR_TYPEDEF(IWinHttpRequestEvents, __uuidof(IWinHttpRequestEvents));
All of this will be wrapped in a C++ namespace:
namespace WinHttp {
// definitions in here
}
If you don't want namespaces, you can do something like:
#import "winhttpcom.dll" no_namespace
Documentation for #import is at https://learn.microsoft.com/en-us/cpp/preprocessor/hash-import-directive-cpp?view=vs-2019
I recently created a VS2015 solution to continue development on a C++ project I had been working on. Whenever I try to build the project, I get hundreds of errors from standard C library header files such as string.h, stdio.h, etc.
To try to get to the root of the problem, I created a new, very basic, VC++ win32 console application project, wondering if I'd see the same compiler errors. Here is the code (ConsoleApplication1.cpp):
#include <string>
#include <iostream>
int main()
{
std::string s = "some data to print...";
std::cout << "Printing: " << s.c_str() << std::endl;
return 0;
}
When I attempt to compile this, I get 150+ errors, like this:
1>------ Build started: Project: ConsoleApplication1, Configuration: Release Win32 ------
1> stdafx.cpp
1>C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(309): error C2144: syntax error: 'int' should be preceded by ';'
1>C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(309): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(311): error C2144: syntax error: 'int' should be preceded by ';'
1>C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(311): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(311): error C2086: 'int _CRTIMP_ALTERNATIVE': redefinition
1> C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(309): note: see declaration of '_CRTIMP_ALTERNATIVE'
1>C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(317): error C2144: syntax error: 'int' should be preceded by ';'
1>C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(317): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(317): error C2086: 'int _CRTIMP_ALTERNATIVE': redefinition
1> C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(309): note: see declaration of '_CRTIMP_ALTERNATIVE'
1>C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(320): error C2144: syntax error: 'int' should be preceded by ';'
1>C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(320): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(320): error C2086: 'int _CRTIMP_ALTERNATIVE': redefinition
1> C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\include\stdio.h(309): note: see declaration of '_CRTIMP_ALTERNATIVE'
....etc
I have tried to 'repair' Microsoft VC++ 2015 Redistributable(x86) via the Windows 'Uninstall or change a program' utility, to no avail. I also tried to repair Visual Studio 2015 as a whole.
I'm on Windows 7.
Anyone have an idea what is going on here? Am I pointed to the wrong include directory or something?
It appears you have (some of) the headers from a previous version of VS installed in your VS2015 folder. The standard headers in VS2015 are stored off in a folder tied to the version of the CRT (something like c:\Program Files (x86)\Windows Kits\10\Include\10.0.10240.0\ucrt). Repairing or reinstalling VS2015 won't fix this.
I think you'll need to uninstall VS2015, completely delete the folder C:\Program Files (x86)\Microsoft Visual Studio 14.0, then reinstall it. This will likely break the other version (VS2013?) that is installed there, so you might want/need to uninstall that version instead, then repair VS2015.
The header that comes with VS2015 does not appear to have the "int _CRTIMP_ALTERNATIVE" listed in some of the error messages at those lines, while the one with VS2013 does.
In VS2013 Community Edition, I had a Win32 VC++ clr project I've been working on. I'm trying to use the CefSharp library, and so through nuget I've imported it.
Following the steps found here I learned I had to change from Win32 to x64 as my 'Active solution platform' to avoid this:
error : CefSharp.Common does not work correctly on 'Win32' platform. You need to specify platform (x86 / x64).
However when I follow those steps and add x64 to my project through the configuration manager, I get the following compilation errors:
1>------ Build started: Project: PROJECTNAME, Configuration: Release x64 ------
1> Main.cpp
1>C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\include\system_error(20): error C2869: 'std::errc' : has already been defined to be a namespace
1>C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\include\system_error(101): error C2146: syntax error : missing ';' before identifier 'generic_errno'
1>C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\include\system_error(101): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\include\system_error(101): fatal error C1903: unable to recover from previous error(s); stopping compilation
I'm not sure what is causing this or how to solve it.
Edit: unlike the case in the question noted in the vote-to-close, the offending code here is CRT code, not mine. Even if it has a problem (which I'm pretty sure it doesn't), I have no way of fixing its source.
We have some legacy memory-leak tracing code that uses some CRT internals (nothing too exotic, essentially _CrtMemBlockHeader which is sort-of documented). While trying to migrate from VS2010 to VS2013 the code seems to cause sporadic build failures, and the offending part can be reduced to this:
#include <windows.h>
#define _CRTBLD
#include <..\crt\src\dbgint.h>
#include <fstream>
void Func()
{
std::ofstream myfile;
myfile << 8;
}
I.e., these 10 lines alone builds fine in VS2010 and in VS2013 give:
c:\program files (x86)\microsoft visual studio
12.0\vc\include\xlocnum(1105): error C2491: 'std::numpunct<_Elem>::id' : definition of dllimport static data member not allowed
I suspect the error message is not accurate - there are indeed several potential definitions of id, none of them at line 1105. There is also a considerable spew of warnings:
1>c:\program files (x86)\microsoft visual studio 12.0\vc\include\xlocnum(1105): warning C4273: 'id' : inconsistent dll linkage
1> c:\program files (x86)\microsoft visual studio 12.0\vc\include\xlocnum(80) : see previous definition of 'public: static std::locale::id std::numpunct<char>::id'
1> c:\program files (x86)\microsoft visual studio 12.0\vc\include\xlocnum(80) : while compiling class template static data member 'std::locale::id std::numpunct<_Elem>::id'
1> with
1> [
1> _Elem=char
1> ]
1> c:\program files (x86)\microsoft visual studio 12.0\vc\include\xlocnum(1185) : see reference to function template instantiation 'const _Facet &std::use_facet<std::numpunct<_Elem>>(const std::locale &)' being compiled
1> with
1> [
1> _Facet=std::numpunct<char>
1> , _Elem=char
1> ]
1> c:\program files (x86)\microsoft visual studio 12.0\vc\include\xlocnum(1179) : while compiling class template member function 'std::ostreambuf_iterator<char,std::char_traits<char>> std::num_put<char,std::ostreambuf_iterator<char,std::char_traits<char>>>::do_put(_OutIt,std::ios_base &,_Elem,std::_Bool) const'
1> with
1> [
1> _OutIt=std::ostreambuf_iterator<char,std::char_traits<char>>
1> , _Elem=char
1> ]
1> c:\program files (x86)\microsoft visual studio 12.0\vc\include\ostream(306) : see reference to class template instantiation 'std::num_put<char,std::ostreambuf_iterator<char,std::char_traits<char>>>' being compiled
1> c:\program files (x86)\microsoft visual studio 12.0\vc\include\ostream(292) : while compiling class template member function 'std::basic_ostream<char,std::char_traits<char>> &std::basic_ostream<char,std::char_traits<char>>::operator <<(int)'
1> c:\users\ofek\documents\visual studio 2013\projects\testcamsys2013\testcamsys2013\source.cpp(10) : see reference to function template instantiation 'std::basic_ostream<char,std::char_traits<char>> &std::basic_ostream<char,std::char_traits<char>>::operator <<(int)' being compiled
1> c:\program files (x86)\microsoft visual studio 12.0\vc\include\fstream(921) : see reference to class template instantiation 'std::basic_ostream<char,std::char_traits<char>>' being compiled
1> c:\users\ofek\documents\visual studio 2013\projects\testcamsys2013\testcamsys2013\source.cpp(9) : see reference to class template instantiation 'std::basic_ofstream<char,std::char_traits<char>>' being compiled
For now I'm pasting the definitions of _CrtMemBlockHeader and some macros around it directly to my code. But still - can anyone see what broke?
I realize it is not fully supported, but one can hope: is there a more robust way of using _CrtMemBlockHeader?
Looking at this error on my system, it seems to be only related to the #define _CRTBLD and the fstream header. The included dbgint.h is irrelevant (you can comment out that #include and still get the same error.
So, this seems to be a problem in the fstream header. Changing the order of inclusion removes the compilation errors:
#include <windows.h>
#include <fstream>
#define _CRTBLD
#include <..\crt\src\dbgint.h>
Perhaps this helps?
I have installed visual studio 2012 on 64 bit windows 7, and trying to build MFC Project, but on first debug always appear error:
Error 1 error C3861: '_T': identifier not found c:\program files (x86)\microsoft visual studio 11.0\vc\atlmfc\include\atlexcept.h 66
Error 3 error C3861: '_T': identifier not found c:\program files (x86)\microsoft visual studio 11.0\vc\atlmfc\include\atlcomcli.h 556
Error 4 error C3861: '_T': identifier not found c:\program files (x86)\microsoft visual studio 11.0\vc\atlmfc\include\atlcomcli.h 589
...
Where those _T macro have to be define? Why those problem appear?
#include <tchar.h> should work. If it is not.. Then try to do this ;
#ifdef _UNICODE
#define _T(x) L ## x
#else /* _UNICODE */
#define _T(x) x
#endif /* _UNICODE */