A Theoretically Correct C++ Compiler

Sanjoy — Tue, 24 May 2011 17:04:07 +0000

I just realized that a C++ compiler can never be theoretically correct. This follows from the fact that C++ templates are Turing Complete (no, really) and the halting problem. We can never say for sure whether a template expression is indeed infinitely recursive or is just taking too long to “parse”.

Sweet, but disappointing.

For those who need to Lint large projects.

Sanjoy — Wed, 24 Nov 2010 05:58:56 +0000

For certain reasons, I had to lint a rather large autoconf based project. While running splint *.c is trivial for a small project, things can get rather convoluted with autoconf‘s intervention, notably when it comes to mentioning include directories on the command line.

The (rather obvious) solution I used was to have make invoke a shell-script instead of the C compiler directly and have the script run splint and redirect its output to some temporary file I could later open. Here is the script, just in case anyone else finds it useful:

#!/bin/zsh

splint_args=""
for arg in "$@"; do
	if [[ $arg =~ '(.*\.c)|(-I.*)' ]]; then
		splint_args="$arg $splint_args"
	fi
done
if [[ -n $splint_args ]]; then
	$splint_args="$splint_args"
	splint $=splint_args &>> /tmp/splint-output
fi
cc $@

Using the script is easy, instead of ./configure --foo=bar --disable-baz, do a CC=/path/to/script LD=ld ./configure --foo=bar --disable-baz. Also, don’t forget to chmod +x the script. Happy Hacking! :)

Playing With Pointers » C++

A Theoretically Correct C++ Compiler

For those who need to Lint large projects.