..during on-demand parsing of CTU"
During CTU, the *on-demand parsing* will read and parse the invocation
list to know how to compile the file being imported. However, it seems
that the invocation list will be parsed again if a previous parsing
has failed.
Then, parse again and fail again. This patch tries to overcome the
problem by storing the error code during the first parsing, and
re-create the stored error during the later parsings.
Reland without test.
Reviewed By: steakhal
Patch By: OikawaKirie!
Differential Revision: https://reviews.llvm.org/D101763