I just compiled the published Q3A source code: it simply works regardless of the used compiler (SuSE 9.3 comes with GCC 3.3.5 20050117). The only thing I had to do was to convert some text files from DOS line endings (0x0d 0x0a) to UNIX line endings (0x0a). This was needed for the 'make' replacement 'code/unix/cons' (which is written in Perl) and for almost all game source code files (already known from the SDK) because the LCC compiler (used for byte code creation) is very picky about line endings in pre-processor directives (#include, #define).
From a demo analysing standpoint the files 'code/qcommon/msg.c', 'code/qcommon/huffman.c', and 'code/client/cl_parse.c' were especially interesting for me. With the GPL license it would be even possible to simply use most of these files in LMPC (which is GPL too).