4 Commits

Author SHA1 Message Date
Peter Klausler
6fac3f7b2e
[flang] Stricter "implicit continuation" in preprocessing
The prescanner performs implicit line continuation when it looks
like the parenthesized arguments of a call to a function-like macro
may span multiple lines.  In an attempt to work more like a
Fortran-oblivious C preprocessor, the prescanner will act as if
the following lines had been continuations so that the function-like
macro could be invoked.

This still seems like a good idea, but a recent bug report on
LLVM's GitHub issue tracker shows one way in which it could trigger
inadvertently and mess up a program.  So this patch makes the
conditions for implicit line continuation much more strict.

First, the leading parenthesis has to have been preceded by an
identifier that's known to be a macro name.  (It doesn't have to
be a function-like macro, since it's possible for a keyword-like
macro to expand to the name of a function-like macro.)  Second,
no macro definition can ever have had unbalanced parentheses in
its replacement text.

Also cleans up some parenthesis recognition code to fix some
issues found in testing, so that a token with leading or trailing
spaces can still be recognized as a parenthesis or comma.

Fixes https://github.com/llvm/llvm-project/issues/63844.

Differential Revision: https://reviews.llvm.org/D155499
2023-07-31 14:22:43 -07:00
Ivan Zhechev
6c1ac141d3 [Flang] Ported test_errors.sh to Python
To enable Flang testing on Windows, shell scripts have to be ported to Python. In this patch the "test_errors.sh" script is ported to python ("test_errors.py"). The RUN line of existing tests was changed to make use of the python script.

Used python regex in place of awk/sed.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D107575
2021-09-06 08:19:42 +00:00
Michael Kruse
58c3f20bbf [flang][windows] Run regression tests under Windows. NFCI.
Allow the lit test suite to run under Windows. This encompasses the following changes:

 * Define `lit_tools_dir` for flang's test configuration
 * Replace `(<command> || true)` idiom with `not <command>`
 * Add `REQUIRES: shell` on tests that invoke a shell script

Reviewed By: awarzynski

Differential Revision: https://reviews.llvm.org/D89368
2021-06-10 05:13:44 -05:00
Peter Steinfeld
5a9497d689 [flang] Allow large and erroneous ac-implied-do's
We sometimes unroll an ac-implied-do of an array constructor into a flat list
of values.  We then re-analyze the array constructor that contains the
resulting list of expressions.  Such a list may or may not contain errors.

But when processing an array constructor with an unrolled ac-implied-do, the
compiler was building an expression to represent the extent of the resulting
array constructor containing the list of values.  The number of operands
in this extent expression was based on the number of elements in the
unrolled list of values.  For very large lists, this created an
expression so large that it could not be evaluated by the compiler
without overflowing the stack.

I fixed this by continuously folding the extent expression as each operand is
added to it.  I added the test .../flang/test/Semantics/array-constr-big.f90
that will cause the compiler to seg fault without this change.

Also, when the unrolled ac-implied-do expression contains errors, we were
repeating the same error message referencing the same source line for every
instance of the erroneous expression in the unrolled list.  This potentially
resulted in a very long list of messages for a single error in the source code.

I fixed this by comparing the message being emitted to the previously emitted
message.  If they are the same, I do not emit the message.  This change is also
tested by the new test array-constr-big.f90.

Several of the existing tests had duplicate error messages for the same source
line, and this change caused differences in their output.  So I adjusted the
tests to match the new message emitting behavior.

Differential Revision: https://reviews.llvm.org/D102210
2021-05-11 10:04:18 -07:00