Blog :: Sune Vuorela – Page 3 – Thoughts, actions and projects

So close, but so far away

Posted on 2016-02-16 by

strcpy_s(dest, strlen(src),src);

1	strcpy_s(dest, strlen(src),src);

Compilers and error messages

Posted on 2016-02-02 by

Sune Vuorela Posted in english, kde, qt

So. I typo’ed up some template code the other day. And once again I learned the importance of using several c++ compilers.

Here is a very reduced version of my code:

#include <utility>
template <typename T> auto foo(const T& t) -> decltype(x.first)
{
    return t.first;
}
int main()
{
   foo(std::make_pair(1,2));
   return 0;
}

#include <utility>

template <typename T> auto foo(const T& t) -> decltype(x.first)

{

return t.first;

}

int main()

{

foo(std::make_pair(1,2));

return 0;

}

And let’s start with the compiler I was testing with first.

MSVC (2013 and 2015)

main.cpp(8): error C2672: 'foo': no matching overloaded function found
main.cpp(8): error C2893: Failed to specialize function template 'unknown-type foo(const T &)'

1 2	main.cpp(8): error C2672: 'foo': no matching overloaded function found main.cpp(8): error C2893: Failed to specialize function template 'unknown-type foo(const T &)'

It is not completely clear from that error message what’s going on, so let’s try some other compilers:

GCC (4.9-5.3)

2 : error: 'x' was not declared in this scope
template <typename T> auto foo(const T& t) -> decltype(x.first)

1 2	2 : error: 'x' was not declared in this scope template <typename T> auto foo(const T& t) -> decltype(x.first)

That’s pretty clear. More compilers:

Clang (3.3-3.7)

2 : error: use of undeclared identifier 'x'
template <typename T> auto foo(const T& t) -> decltype(x.first)

1 2	2 : error: use of undeclared identifier 'x' template <typename T> auto foo(const T& t) -> decltype(x.first)

ICC (13)

example.cpp(2): error: identifier "x" is undefined
template <typename T> auto foo(const T& t) -> decltype(x.first)

1 2	example.cpp(2): error: identifier "x" is undefined template <typename T> auto foo(const T& t) -> decltype(x.first)

(Yes. I mistyped the variable name used for decltype. Replacing the x with t makes it build).

Thanks to http://gcc.godbolt.org/ and http://webcompiler.cloudapp.net/ for testing with various compilers.

KDE at Qt World Summit

Posted on 2015-10-05 by

Sune Vuorela Posted in english, kde, qt

So. KDE has landed at Qt World Summit.

You can come and visit our booth and …

hear about our amazing Free Qt Addons (KDE Frameworks)
stories about our development tools
meet some of our developers
Talk about KDE in general
Or just say hi!

KDE – 19 years of Qt Experience.

I accidentally the Debian menu

Posted on 2015-09-04 by

Sune Vuorela Posted in debian, english

So quite some time ago, I filed this. After some going back and forth, it lead to this. And finally we have a conclusion. It took only two years, but now we are there. Let’s continue make Debian rock.

Debconf 2015 – 7

Posted on 2015-08-20 by

Sune Vuorela Posted in debian, english

The other day, the main talk was “Lets encrypt”, today it was “Let’s reproduce”

Debconf 2015 – 6

Posted on 2015-08-20 by

Sune Vuorela Posted in debian, english, kde

There is more people with blue hair at Debconf than at an average Akademy. KDE – we need to do better :)

Debconf 2015 – 5

Posted on 2015-08-19 by

Sune Vuorela Posted in debian, english

Watching people figuring out how to use a Danish cheese slicer is kind interesting. But by using enough force most people succeeding in getting a lump of cheese.