Commit Graph

2 Commits

Author SHA1 Message Date
Andrzej Warzynski d18a9aeae9 [flang] Make the frontend driver error out when requesting multiple actions
With this change, the following invocations will be treated as errors
(multiple actions are specified):
```
$ flang-new -fc1 -E -fsyntax-only file.95
$ flang-new -fc1 -fsyntax-only -fdebug-dump-symbols file.95
```
In the examples above it is not clear whether it is `-fsyntax-only` or
the other action that is run (i.e. `-E` or `-fdebug-dump-symbols`). It
makes sense to disallow such usage. This should also lead to cleaner and
clearer tests (the `RUN` lines using `%flang_fc1` will only allow one
action).

This change means that `flang-new -fc1` and `clang -cc1` will behave
differently when multiple action options are specified. As frontend
drivers are mostly used by compiler developers, this shouldn't affect or
confuse the compiler end-users. Also, `flang-new` and `clang` remain
consistent.

Tests are updated accordingly. More specifically, I've made sure that
every test specifies only one action. I've also taken the opportunity to
simplify "multiple-input-files.f90" a bit.

Differential Revision: https://reviews.llvm.org/D111781
2021-12-17 10:05:28 +00:00
peter klausler 3265b93363 [flang] Extension: reduced scope for some implied DO loop indices
The index of an implied DO loop in a DATA statement or array
constructor is defined by Fortran 2018 to have scope over its
implied DO loop.  This definition is unfortunate, because it
requires the implied DO loop's bounds expressions to be in the
scope of the index variable.  Consequently, in code like

  integer, parameter :: j = 5
  real, save :: a(5) = [(j, j=1, j)]

the upper bound of the loop is a reference to the index variable,
not the parameter in the enclosing scope.

This patch limits the scope of the index variable to the "body"
of the implied DO loop as one would naturally expect, with a warning.
I would have preferred to make this a hard error, but most Fortran
compilers treat this case as f18 now does.  If the standard
were to be fixed, the warning could be made optional.

Differential Revision: https://reviews.llvm.org/D108595
2021-08-24 09:34:18 -07:00