[flang][runtime] Handle NAN(...) in namelist input (#153101)

The various per-type functions for list-directed (including namelist)
input editing all call a common function to detect whether the next
token of input is the name of a namelist item. This check simply
determines whether this next token looks like an identifier followed by
'=', '(', or '%', and this fails when the next item of input is a NAN
with parenthesized stuff afterwards. Make the check smarter so that it
ensures that any upcoming possible identifier is actually the name of an
item in the namelist group. (And that's tricky too when the group has an
array item named "nan" and the upcoming input is "nan("; see the
newly-added unit test case.)

Fixes https://github.com/llvm/llvm-project/issues/152538.

more

0 files changed, 0 insertions, 0 deletions