Category Archives: C++

C++ Const Constructability

Posted on March 14, 2020 by Ofek Shilon

[Inspired by CppQuiz #264] Take this code snippet: It fails to compile in gcc, with: error: ‘const struct C’ has no user-provided default constructor and the implicitly-defined constructor does not initialize ‘int C::i’ Clang and icc give similar error messages. … Continue reading →

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On OMP_WAIT_POLICY

Posted on November 3, 2017 by Ofek Shilon

Some years ago I encountered a crash that I reduced down to the following toy code, composed of a dll: and a console app: As emphasized and commented, FreeLibrary causes a crash – typically (but not always) an access violation, … Continue reading →

Posted in C++, VC++ | 2 Comments

CMake Rants

Posted on August 30, 2016 by Ofek Shilon

CMake is a highly popular ‘meta-build’ system: it is a custom declarative syntax that is used to generate build scripts for all major OSs and compilers (e.g., VS solutions and projects). Designing such a system is a formidable task, but … Continue reading →

Posted in C++ | 19 Comments

Executing Code Once Per Thread in an OpenMP Loop

Posted on June 10, 2014 by Ofek Shilon

Take this toy loop: Now suppose you want to run some preparation code once per thread – say, SetThreadName, or SetThreadPriority or whatnot.  How would you go about that? If you code it before the loop the code would execute … Continue reading →

Posted in C++, VC++ | 5 Comments

x86/x64 Numerical differences – Correction

Posted on February 19, 2014 by Ofek Shilon

In a previous post a truncation scheme was suggested, to circumvent x86/x64 differences in math library implementations: Since then, I accumulated some mileage with the scheme and have come to understand that line 8: -is flawed. Since we drop the … Continue reading →

Posted in Algorithms, C++, VC++ | Leave a comment

C++ Template Meta Programming is Still Evil

Posted on September 1, 2012 by Ofek Shilon

I won’t include a meta-programming intro paragraph here, since if you’re not familiar with it – I sincerely hope you stay that way. If you insist, get an idea online or read the book (it’s a good read, but can’t … Continue reading →

Posted in C++ | 36 Comments

Ternary Operator and Type Compatibility

Posted on June 17, 2010 by Ofek Shilon

The (?,:) operator, as in – is commonly referred to as the Ternary Operator. (It is a common abuse of terminology: a ternary operator is one that operates on three arguments. This particular ternary operator is the Conditional Expression operator.)  … Continue reading →

Posted in C++ | 4 Comments