Why doesn't this compile? (VC++ 2015, #pragma omp flush) - c++

Here's a minimal case. Compile with "/openmp" on Visual C++ 2015.
#include <vector>
void main()
{
bool foo = false;
#pragma omp flush (foo)
std::vector<int> bar;
}
I get:
C2146 syntax error : missing ';' before identifier 'bar'
C2275 'std::vector<int,std::allocator<_Ty>>' : illegal use of this type as an expression
C2065 'bar' : undeclared identifier
If I comment out the #pragma, the error goes away.
If I replace std::vector with int, the error goes away.
If I put a ; on a line by itself below the #pragma, the error goes away.

The concise answer to the question "Why doesn't this compile?" is "it's a compiler bug". The bug report at:
https://connect.microsoft.com/VisualStudio/feedbackdetail/view/2420614
has been closed as "fixed".... "this item has been fixed in the current or upcoming version of this product [Visual Studio 2015]".

Related

C++11 compiler error when using decltype(var) followed by internal type of "var"

I'm using Visual C++ 2010, and here's my code snippet:
std::set<int> s;
decltype(s)::value_type param = 0;
I got the following error message, anyone can help me?
> error C2039: 'value_type' : is not a member of '`global namespace''
> error C2146: syntax error : missing ';' before identifier 'param'
This is a Visual Studio bug that was raised last year on Connect. It is issue 757545 ("Cannot use decltype before scope operator").
The issue has a workaround listed alongside it that is effectively the same as #iammillind's, except it uses std::identity that was removed from <functional> shortly prior to the publication of C++11, for whatever reason. (std::common_type with one template parameter is equivalent; std::remove_reference is the same in some cases.)
I see that with g++ 4.7.2 version, the code compiles fine. So it could be a compiler bug in MSVS.
For time being you can try below trick:
#ifdef COMPILER_BUG_STILL_THERE
template<typename T> struct Get { typedef T type; };
#define DECLTYPE(VAR) Get<decltype(VAR)>::type
#else
#define DECLTYPE(VAR) decltype(VAR)
#endif
Use it as:
DECLTYPE(s)::value_type param = 0;
Disclaimer: Ofcourse with this trick, you may have to use typename when inside templates. For that you can have 1 more macro such as #define TDECLTYPE(VAR) typename DECLTYPE(VAR)

member hook implementation for splay_multiset in Boost::Intrusive

I was implementing boost::intrusive for one of my project on visual C++ 2008 and i stumbled upon a problem. i am using splay hooks for splay_multiset containers. I have defined splay hook publically under MyClass (code below).
#include <boost/intrusive/unordered_set.hpp>
#include <boost/intrusive/splay_set.hpp>
#include <iostream>
using namespace boost::intrusive;
class MyClass
{
int int_;
public:
MyClass(int i)
: int_(i)
{}
splay_set_member_hook<link_mode<normal_link> > memberSplayHook;
//**OPTION-1**
//PROBLEM CODE SEGMENT ++
//typedef member_hook<MyClass, splay_set_member_hook<link_mode<normal_link> >, &MyClass::memberSplayHook> MemberOption;
//typedef splay_multiset<MyClass, MemberOption> MemberMultiSet;
//PROBLEM CODE SEGMENT --
MemberMultiSet mmset;
};
//**OPTION-2**
//WORKING CODE SEGMENT ++
typedef member_hook<MyClass, splay_set_member_hook<link_mode<normal_link> >, &MyClass::memberSplayHook> MemberOption;
typedef splay_multiset<MyClass, MemberOption> MemberMultiSet;
//WORKING CODE SEGMENT --
int main()
{
return 0;
}
The problem is, to use splay_multiset, whatever option i choose (either option-1 or 2, mention in code), in both cases i see compilation errors.
When Option-1 is enabled (option-2 is commented), i see errors below:
1>d:\projects\sampleproject\sample.cpp(21) : error C2327: 'MyClass::memberSplayHook' : is not a type name, static, or enumerator
1>d:\projects\sampleproject\sample.cpp(21) : error C2065: 'memberSplayHook' : undeclared identifier
1>d:\projects\sampleproject\sample.cpp(22) : error C3203: 'member_hook' : unspecialized class template can't be used as a template argument for template parameter 'O1', expected a real type
While, when Option-2 is enabled (option-1 is commented out), i dont see undeclared identifier error msg as these errors coming with option-1. But i do see errors like below (which are obvious).
1>d:\projects\sampleproject\sample.cpp(25) : error C2146: syntax error : missing ';' before identifier 'mmset'
1>d:\projects\sampleproject\sample.cpp(25) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
My question is why i am getting error in first case? What can i do to get pass this issue?
Boost member hooks have (always?) been broken, since they don't compile with Visual C++.
I don't have a VS at hand to check for the precise error message so I might be wrong (but reading 'member hooks' and 'Visual C++' always triggers 'there's a problem'-mode), but do try to check this:
http://permalink.gmane.org/gmane.comp.lib.boost.user/56875
EDIT: Don't take the headline literally -- the same applies to Visual C++ 2010 and 2012. All my member hooks use this workaround; at some point I might even try to understand what it does, or more importantly, how to package it into a more comfortable setup for less "I need to find a previous implementation of this workaround so I can copy-and-modify it"...

VS2008 C++ "interface" as a parameter name fails to compile

As the title says, I'm getting a compiler error in a VS2008 C++ program. I'm not sure how better to describe my problem than in code. The following compiles unless I uncomment the TEST line.
#include <windows.h>
#include <iostream>
using namespace std;
//#define TEST //<-- uncomment for error
#ifdef TEST
void test(void* interface)
{
return;
}
#endif
int main()
{
cout << "Hello World" << endl;
system("PAUSE");
return(0);
}
When uncommented I get the following errors:
1>main.cpp(7) : error C2332: 'struct' : missing tag name
1>main.cpp(7) : error C2144: syntax error : '<unnamed-tag>' should be preceded by ')'
1>main.cpp(7) : error C2144: syntax error : '<unnamed-tag>' should be preceded by ';'
1>main.cpp(7) : error C2059: syntax error : ')'
1>main.cpp(8) : warning C4094: untagged 'struct' declared no symbols
1>main.cpp(8) : error C2143: syntax error : missing ';' before '{'
1>main.cpp(8) : error C2447: '{' : missing function header (old-style formal list?)
This is unmanaged code, so I'm not sure what the issue with the word interface is. Is there any way to get this code to compile as is, or do I have to change every instance of the term interface to something else?
Thanks!
If your code needs to include Windows.h then you should avoid using the name interface as it's reserved for the use that the Windows SDK has reserved for it (essentially it's a synonym for the keyword struct). There are probably hacks to work around that problem (you could #undef interface after including the SDK headers), but you should probably avoid using that identifier.
The word interface is reserved by MSVC++, as it is a non-standard keyword added by Microsoft Compiler, which is used to define interface in MSVC++.
So use a different name for the parameter, something like this:
#ifdef TEST
void test(void* test_interface)
{
return;
}
#endif

C++ code compiles in CentOS g++, but not in Visual studio 2008

I have a problem: My codes work well in CentOS g++, but when I compile them in visual studio 2008, the visual studio tells me errors like below:
1.c:\program files (x86)\microsoft visual studio 9.0\vc\include\codeanalysis\sourceannotations.h(19) : error C2144: syntax error : '__w64 unsigned int' should be preceded by '}'
2.error C2143: syntax error : missing '}' before 'namespace'.
My file coding is UTF-8. Should I change them in Unicode all, I change some error file in Unicode,it still has errors like above.
below are some sourecode:
#ifndef ENRC_CODE_DEFS_H
#define ENRC_CODE_DEFS_H
enum ENReturnCode
{
ENRC_SUCCESS = 0,
ENRC_FAILED,
ENRC_NODATA,
ENRC_CONFIG_NOT_AVAILABLE,
ENRC_INVALID_SUBSCRIBE_ID,
ENRC_INVALID_SUBSCRIBE_CONDITION,
ENRC_INVALID_SUBSCRIBER,
ENRC_INVALID_PARAMETER,
ENRC_THREAD_RUNNING,
ENRC_SUBSCRIBE_LIST_EMPTY,
ENRC_OUT_OF_MEMORY // 10
}
e:\my_code\cppcommon\include\errordefs.h(5) : error C2143: syntax error : missing ';' before 'enum [tag]'
next:
#ifndef EN_SMS_SRC_TAO2CPP_H_
#define EN_SMS_SRC_TAO2CPP_H_
#include "SystemMonitorMasterServiceC.h"
#include "SystemMonitorSlaveServiceC.h"
#include "CommonDefs.h"
#include "SystemMonitorServiceDataDefs.h"
namespace EN
{
namespace SMS
{
template < typename _Ty, typename _Cy>
inline
void Tao2Cpp_Enum(_Ty taoValue, _Cy &cppValue)
{
cppValue = (_Cy)taoValue;
}
error C2143: syntax error : missing '}' before 'namespace'
A lot of errors like above.
Thanks. I waste some time to make it easy to read.
You need a semi-colon in the enum declaration:
enum ENReturnCode
{
...
};

Boost Unit Testing and Visual Studio 2005/Visual C++ and the BOOST_AUTO_TEST_SUITE(stringtest) namespace?

I'm reading this article on the Boost Unit Testing Framework.
However I'm having a bit of trouble with the first example, my guess is that they left something out (something that would be obvious to hardcore C++ coders) as IBM often does in their articles. Another possibility is that my Visual Studio 2005 C++ compiler is just too old for the example.
#include "stdafx.h"
#define BOOST_TEST_MODULE stringtest
#include <boost/test/unit_test.hpp>
//#include "mystring.h"
BOOST_AUTO_TEST_SUITE(stringtest) // name of the test suite is stringtest
BOOST_AUTO_TEST_CASE(test1)
{
/*
mystring s;
BOOST_CHECK(s.size() == 0);
*/
BOOST_CHECK(0 == 0);
}
BOOST_AUTO_TEST_CASE(test2)
{
/*
mystring s;
s.setbuffer("hello world");
BOOST_REQUIRE_EQUAL('h', s[0]); // basic test
*/
BOOST_CHECK(0 == 0);
}
BOOST_AUTO_TEST_SUITE_END()
To me the BOOST_AUTO_TEST_SUITE and BOOST_AUTO_TEST_CASE lines look a little suspect (especially since they don't have quotes around the arguments, and they are undeclared identifiers...but this probably means they are macros and I'm not certain I understand the concept or if that is available in VC++ 8.0)...
#ifdef _MYSTRING
#define _MYSTRING
class mystring {
char* buffer;
int length;
public:
void setbuffer(char* s) { buffer s = s; length = strlen(s); }
char& operator[ ] (const int index) { return buffer[index]; }
int size() {return length; }
}
#endif
Is there any reason why this code won't work?
1>c:\users\andy\documents\visual studio 2005\projects\unittesttests\unittesttests\unittesttests.cpp(7) : error C2065: 'stringtest' : undeclared identifier
1>c:\users\andy\documents\visual studio 2005\projects\unittesttests\unittesttests\unittesttests.cpp(9) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\users\andy\documents\visual studio 2005\projects\unittesttests\unittesttests\unittesttests.cpp(9) : error C2146: syntax error : missing ';' before identifier 'BOOST_AUTO_TEST_CASE'
1>c:\users\andy\documents\visual studio 2005\projects\unittesttests\unittesttests\unittesttests.cpp(9) : error C2065: 'test1' : undeclared identifier
1>c:\users\andy\documents\visual studio 2005\projects\unittesttests\unittesttests\unittesttests.cpp(10) : error C2448: 'BOOST_AUTO_TEST_CASE' : function-style initializer appears to be a function definition
1>c:\users\andy\documents\visual studio 2005\projects\unittesttests\unittesttests\unittesttests.cpp(18) : error C2065: 'test2' : undeclared identifier
1>c:\users\andy\documents\visual studio 2005\projects\unittesttests\unittesttests\unittesttests.cpp(19) : error C2448: 'BOOST_AUTO_TEST_CASE' : function-style initializer appears to be a function definition
1>c:\users\andy\documents\visual studio 2005\projects\unittesttests\unittesttests\unittesttests.cpp(29) : fatal error C1004: unexpected end-of-file found
Looks correct to me. My Boost.Test code looks the same way. I'm running VS2008, but I know it works in 2005 as well.
Seems like your problem lies elsewhere.
If you use precompiled headers (and why do you do that in such a small test program?), shouldn't stdafx.h be included as the very first thing in the file?
And what is the first line for? You don't seem to use it, and _MYSTRING is a reserved name in C++ (everything that begins with underscore followed by a capital letter is off limits)