C source-to-source compiler enhancement from within

A new research report describing shnell has now appeared on HAL:

https://hal.inria.fr/hal-02998412

We show how locally replaceable code snippets can be used to easily specify and prototype compiler and language enhancements for the C language that work by local source-to-source transformation. A toolbox implements the feature and provides many directives that can be used for compile time configuration and tuning, code unrolling, compile time expression evaluation and program modularization. The tool is also easily extensible by simple filters that can be programmed with any suitable text processing framework.

gcc doesn’t inline position independent code properly

When compiling position independent code, PIC, the gcc compiler fails to inline many functions that have an external name, that is that are not declared static. While this is conforming to the C standard, this is a complete blow to a lot of optimization efforts that I have put into my code in many places.

Unicode operators for C

C11 has added a certain level of Unicode support to C, but I think for C2x it will be time to go a step further and put C in line with general usage of special characters as they are normalized by Unicode. In particular, it is time to get rid of restrictions in operator naming that stem from the limited availability of special characters 30 years ago, when all of this was invented.

Update on Modular C

Some time ago I had advertised for one of my new toys, Modular C, an extension of the C language aiming for modularity, and, more generally for an easier use. Since then it has gained some new features and I have rounded up some edges, so you all should definitively have another look 🙂

Among the new features are

• complete Unicode support (identifiers, operators)
• finite code unrolling (foreach directive)
• programmable expression contexts (e.g for modulo arithmetic or string operations)

Also, there is now some concise documentation, at

http://cmod.gforge.inria.fr/doxygen/

Modular C

Since decades, C is one of the most widely used programming languages, and is used successfully for large software projects that are ubiquitous in modern computing devices of all scales. For many programmers, software projects and commercial enterprises C has advantages (relative simplicity, faithfulness to modern architectures, backward and forward compatibility) that largely outweigh its shortcomings. Among these shortcomings, is a lack of two important closely related features: modularity and reusability. C misses to encapsulate different translation units (TU) properly: all symbols that are part of the interface of a software unit such as functions are shared between all TU that are linked together into an executable.