In free form source, pedantic mode will elicit portability warnings
about missing spaces when a token string ends with a character that
can be in an identifier and there is no space between that last token
character and a following character that can also be part of an identifier.
This behavior doesn't really work well for the token strings that are
parsed for edit descriptors in FORMAT statements. For example, the
'F' in FORMAT(F7.3) is followed by a digit, but obviously no space is
necessary. Free form or not, FORMATs are their own odd little world.
This patch adds trailing blanks to these FORMAT edit descriptor token
parsers to disable the missing space check, and extends the documentation
for token string parsing to explain why this technique works.
Differential Revision: https://reviews.llvm.org/D129023
Extend "extension<LanguageFeature>()" to incorporate an explanatory
message better than the current generic "nonstandard usage:".
Differential Revision: https://reviews.llvm.org/D122035
The parsing of I/O units uses look-ahead to discriminate between
keywords, variables and expressions as part of distinguishing internal
from external I/O. The look-ahead was inaccurate for variables that
appear as the initial parts of expressions.
Differential Revision: https://reviews.llvm.org/D95743
READ(CVAR)[,item-list] with a character variable CVAR
could be parsed as an unformatted READ from an internal
unit or as a formatted READ from the default external unit
with a needlessly parenthesized variable format. We parse
it as the former, but Fortran doesn't have unformatted
internal I/O.
Differential revision: https://reviews.llvm.org/D90493
Peter Klausler