On Wed, Dec 18, 2013 at 02:32:01PM +0100, Bernd Edlinger wrote: > I wonder if the GMPINC="" is still necessary, as the actual host g++ > invocation also has GMP-directories > but does not use them because of the -DGENERATOR_FILE.
The issue isn't finding gmp.h, it's finding other host headers you don't want. Clearly, --with-gmp and similar options are for finding host libraries and headers. install.texi even says so! To give an example of what can go wrong, suppose someone specifies --with-gmp=/sysroot_for_host for an installed gmp. Now I know that it's unnecessary to specify --with-gmp if it's at the default install location, but many people blindly follow recipes. What's more, specifying --with-gmp to the default works fine when build == host. So it doesn't seem wrong to me to specify --with-gmp (even needlessly to the default) when build != host. The trouble is that GMPINC is then /sysroot_for_host/include, which is where you find all the other host headers, not just gmp.h.. -- Alan Modra Australia Development Lab, IBM
