On 11 May 2017 at 10:13, Boris Kolpackov wrote: > Hi, > > In the build system I am working on we are looking at always performing > the preprocessing and then C/C++ compilation as two separate gcc/g++ > invocations. The main reason is support for distributed compilation but > see here[1] for other reasons. > > I realize that tools like ccache/distcc have been relying on this for > a while (though see the 'direct' mode in ccache and 'pump' in distcc). > However, some compilers apparently do not support this (for example, > VC; see the above link for details).
Here's a nickel kid, get yourself a better compiler ;-) http://dilbert.com/strip/1995-06-24 > So I wonder, in the context of GCC, if this is just a hack that happens > to work "for now" or if this is a feature that is expected to continue > to work? It's absolutely a supported feature. Why else do you think the manual would discuss so many options for preprocessing, and options for compiling preprocessed code? https://gcc.gnu.org/onlinedocs/gcc/Overall-Options.html seems quite explicit. > Also, has anyone seen/heard of any real-world issues with compiling > preprocessed source code? There are very occasional bugs where compiling the original source code behaves slightly differently, e.g. regarding what is considered a system header, but it usually only affects warnings or errors, not code generation. And nothing that would mean separate preprocessing and compilation shouldn't be relied on.
