liberation-circuit

I use strace(1) look for stat(2) syscalls that fail with ENOENT. An advantage of this approach is that I do not have to imitate the C preprocessor, so parser differentials can never happen. The following default.o.do file from my blog post [1] handles the case: #!/bin/sh redo-ifchange $2.c strace -e stat,stat64,fstat,fstat64,lstat,lstat64 -f 2>&1 >/dev/null\ gcc $2.c -o $3 -MD -MF $2.deps\ |grep '1 ENOENT'\ |grep '\.h'\ |cut -d'"' -f2 2>/dev/null\ >$2.deps_ne read d <$2.deps redo-ifchange ${d#*:} while read -r d_ne; do redo-ifcreate $d_ne done <$2.deps_ne chmod a+x $3 This approach is also used for building Liberation Circuit if strace is installed [2]. I think the compiler should output the necessary information. To quote Jonathan de Boyne Pollard [3]: > As noted earlier, no C or C++ compiler

There exists DJB's redo approach [0], which i implemented [1], where dependencies and non-existence dependencies are only recorded after the build. A typical dofile is a shell script, so you do not need to learn another language. Targets also automatically depend on their own build rules (I have seen such a thing only in makefiles authored by DJB). I wrote a blog post to show how to integrate dependency output for both dependency and non-existence dependency generation [2]. The game “Liberation Circuit” can be built with my redo implementation; you can output a dependency graph usable with Graphviz [4] using “redo-dot”. There is only one other redo implementation that I would recommend, the one from Jonathan de Boyne Pollard [5], who rightly notices that compilers should output information about non-existence dependencies [6]. I would not

An issue I have with make is that it can not handle non-existence dependencies. DJB noted this in 2003 [1]. To quote myself on this [2]: > Especially when using C or C++, often target files depend on nonexistent files as well, meaning that a target file should be rebuilt when a previosly nonexistent file is created: If the preprocessor includes /usr/include/stdio.h because it could not find /usr/local/include/stdio.h, the creation of the latter file should trigger a rebuild. I did some research on the topic using the repository of the game Liberation Circuit [3] and my own redo implementation [4] … it turns out that a typical project in C or C++ has lots of non-existence dependencies. How do make users handle non-existence dependencies – except for always calling “make clean”? [1] http://cr.yp.to/redo/honest-nonfile.html [2] http://news.d