This is due to calling the configure script via `make' (within the
top-level `configure' wrapper script). The same can happen for all
other secondary make targets that are used to only modify the
primary one, e.g., `make setup devel'.
* builds/dos/detect.mk (emx, turboc, watcom, borlandc, borlandc16),
builds/os2/detect (visualage, watcom, borlandc, devel),
builds/unix/detect.mk (devel, lcc, unix), builds/windows/detect.mk
(visualc, watcom, visualage, lcc, mingw32, bcc32, devel-bcc,
devel-gcc): Use no-op recipe.