The include guard symbol is `FORTRAN_$dir_$file_H_` where $dir is the
subdirectory of `lib` and $file is the basename of the header file.
Those names are mapped to uppercase and hyphens are replaced by
underscores.
Original-commit: flang-compiler/f18@ac9c0e7106
Reviewed-on: https://github.com/flang-compiler/f18/pull/75
The classes that were segregated into format-specification.h have
also been grouped into a new Fortran::format namespace.
Code added to tools/f18/f18.cc to run a minimal visitor over
the parse trees resulting from successful parses so that any
future build problems with Walk() will be caught earlier.
Rearrange Walk instances, keep format:: ones together.
Original-commit: flang-compiler/f18@685ddb91ce
Reviewed-on: https://github.com/flang-compiler/f18/pull/22