I will echo what others have said: a better algorithm is going to win in terms of performance gains. That said, I work in image processing, which as a problem domain can be stickier. For example, many years ago I had a chunk of code that looked like this: void FlipBuffer(unsigned char *start, unsigned char … Read more
There appears to be a related bug report, Bug 59659 – large zero-initialized std::array compile time excessive. It was considered “fixed” for 4.9.0, so I consider this testcase either a regression or an edgecase not covered by the patch. For what it’s worth, two of the bug report’s test cases1, 2 exhibit symptoms for me … Read more
With help of a compile-time integer list: #include <cstdlib> template <size_t… n> struct ct_integers_list { template <size_t m> struct push_back { typedef ct_integers_list<n…, m> type; }; }; template <size_t max> struct ct_iota_1 { typedef typename ct_iota_1<max-1>::type::template push_back<max>::type type; }; template <> struct ct_iota_1<0> { typedef ct_integers_list<> type; }; We could construct the tail simply by … Read more
With help of a compile-time integer list: #include <cstdlib> template <size_t… n> struct ct_integers_list { template <size_t m> struct push_back { typedef ct_integers_list<n…, m> type; }; }; template <size_t max> struct ct_iota_1 { typedef typename ct_iota_1<max-1>::type::template push_back<max>::type type; }; template <> struct ct_iota_1<0> { typedef ct_integers_list<> type; }; We could construct the tail simply by … Read more
Today I have bumped into this problem and solved it in the following way. I pressed “Reset defaults” button everywhere I could find it in Eclipse settings (for example, Preferences/C++/Build/Settings/Discovery). After that the error disappeared and the code compiled successfully.
As i said in the comment, the problem is due to cyclic dependency. In particular, your Student.hpp includes –> Grad.hpp which in turn includes –> Core.hpp which finally includes –> Student.hpp So as you can see from above, you ended up where you started, namely at Student.hpp. This is why it is called cyclic dependency. … Read more
Use -Wconversion — the problem is an implicit cast (conversion) from long x to short when the function f(short x) is called [not printf], and -Wconversion will say something like “cast from long to short may alter value”. .. Edit: just saw your note. -Wconversion results in a warning for me, using g++ 4.3.2 on … Read more
Encoding Blues You cannot use UTF-16 for source code files; because the header you are including, <iostream>, is not UTF-16-encoded. As #include includes the files verbatim, this means that you suddenly have an UTF-16-encoded file with a large chunk (approximately 4k, apparently) of invalid data. There is almost no good reason to ever use UTF-16 … Read more
Turns out there isn’t a way to reliably recover the semaphore. Sure, anyone can post_sem() to the named semaphore to get the count to increase past zero again, but how to tell when such a recovery is needed? The API provided is too limited and doesn’t indicate in any way when this has happened. Beware … Read more