https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86211
Arnaud Charlet <charlet at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |charlet at gcc dot gnu.org --- Comment #1 from Arnaud Charlet <charlet at gcc dot gnu.org> --- As you said, this combination isn't guaranteed to work, although I'm surprising by the gcc command line you showed, which doesn't include -Iada/libgnat or -I../../gcc/ada/libgnat as per ADA_INCLUDES in gcc-interface/Make-lang.in: ADA_INCLUDES = -nostdinc -I- -I. -Iada/generated -Iada -I$(srcdir)/ada -I$(srcdir)/ada/gcc-interface -Iada/libgnat -I$(srcdir)/ada/libgnat So I'd suggest double checking your source tree here, maybe you have some local changes that are modifying ADA_INCLUDES?