https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120106
--- Comment #21 from Nicolas Boulenguez <nicolas at debian dot org> --- > Why to pass GNATMAKE_FOR_BUILD to sub-configures since they do not use it? I have imitated the transmission of existing _FOR_BUILD variables by other languages in the same build system. I have not been surprised because ./configure often substitutes 'VAR=@VAR@' when transforming Makefile.in to Makefile, also computing at configure time variables only used at build time. As far as I know, the intent is to allow implementors to override 'make VAR=testvalue' when debugging, while ensuring that, by default, all steps of 'make foo && make bar && su make install' use the same configuration. For the avoidance of doubt, I am just answering your question, not arguing in a way or another.
