Category Archives: VC++

Vector Deleting Destructor and Weak Linkage

Posted on June 13, 2014 by Ofek Shilon

Now that the discussions on weak linker symbols and vector deleting destructors are in place, it is time to discuss a fact that might seem esoteric but has far reaching implications. After that, it is time to ask for your … Continue reading →

Posted in VC++ | 9 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

On Vector Deleting Destructors and some new/delete internals

Posted on June 9, 2014 by Ofek Shilon

A word is due on vector deleting destructors – previously mentioned as the only functions that got weakly bound by the linker. The usual disclaimers apply: everything that follows is my own investigation, in code and online. Nothing here is … Continue reading →

Posted in VC++ | 6 Comments

Setting a Watch on Wide Registers in VS

Posted on June 3, 2014 by Ofek Shilon

General-purpose registers can be watched from the watch window pretty much as regular variables: (the ‘$’ prefix is optional, but is recommended by MS – probably as means to minimize clashes with code variables.) It is less known that you … Continue reading →

Posted in Debugging, VC++ | Leave a comment

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

Linker Weak Symbols

Posted on February 10, 2014 by Ofek Shilon

C++’s One-Definition-Rule roughly states that In the entire program, an object or non-inline function cannot have more than one definition; if an object or function is used, it must have exactly one definition. Which sounds like a good idea – … Continue reading →

Posted in VC++ | 3 Comments

x86/x64 Library Numerical differences

Posted on February 1, 2014 by Ofek Shilon

There are many online sets of examples of 64 bit migration pitfalls, but I recently came across two that that appear not to be mentioned elsewhere. First, downright compiler bugs.  We still have those and some raise their head only … Continue reading →

Posted in VC++ | 3 Comments

Another Look at the VS2012 Auto Vectorizer

Posted on October 8, 2013 by Ofek Shilon

A while ago I did some experimenting with (than beta) VS2012. After these experiments our team migrated to the 2012 IDE but kept to the 2010 toolset. Since then much had happened: an official VS2012 launch + 4 updates, rather … Continue reading →

Posted in VC++ | Leave a comment

Find Where Types are Passed by Value

Posted on September 13, 2013 by Ofek Shilon

Say you’re working on a large code base, and you came across several instances where some type of non-negligible size was passed as argument by value – where it was more efficient to pass by const reference. Fixing a few … Continue reading →

Posted in VC++ | 2 Comments

Discovering Which Projects Depend on One

Posted on August 11, 2013 by Ofek Shilon

I am working with several large-ish (100+ project) solutions – and at this scale, dependency management is a very real issue. While you can easily view (and set) the dependencies of a project by viewing its references, there is no … Continue reading →

Posted in VC++, Visual Studio | 2 Comments