Make-lang.in contains the following bit:
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# .o: .h dependencies.
# Everything depends on gfortran.h, but only a few files depend on
# the other headers. So at some point we'll have to split out
# which objects depend on what. FIXME
# TODO: Add dependencies on the backend/tree header files
$(F95_PARSER_OBJS): fortran/gfortran.h fortran/intrinsic.h
fortran/match.h \
fortran/parse.h \
$(CONFIG_H) $(SYSTEM_H) $(TM_H) $(TM_P_H) coretypes.h \
$(RTL_H) $(TREE_H) $(TREE_DUMP_H) $(GGC_H) $(EXPR_H) \
$(FLAGS_H) output.h $(DIAGNOSTIC_H) errors.h $(FUNCTION_H)
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I just noticed that arith.h isn't listed in there, despite the fact that
simplify.c (which is part of $(F95_PARSER_OBJS) includes it. That's a
bug, yes?
- Brooks