A CHARACTER variable used as an output format may contain
unquoted tab characters, which are treated as if they had
been quoted. This is an extension supported by all other
Fortran compilers to which I have access.
Differential Revision: https://reviews.llvm.org/D112350
Don't try to convert INTEGER argument expressions to the kind of
the dummy argument when performing generic resolution; specific
procedures may be distinguished only by their kinds.
Differential Revision: https://reviews.llvm.org/D112240
Allocatable dummy arguments can be used to distinguish
two specific procedures in a generic interface when
it is the case that exactly one of them is polymorphic
or exactly one of them is unlimited polymorphic. The
standard requires that an actual argument corresponding
to an (unlimited) polymorphic allocatable dummy argument
must also be an (unlimited) polymorphic allocatable, so an
actual argument that's acceptable to one procedure must
necessarily be a bad match for the other.
Differential Revision: https://reviews.llvm.org/D112237
The Fortran 2018 standard defines the concept of simple contiguity
in subclause 9.5.4 as a characteristic of arrays. So that scalars
may also be used in contexts where simply contiguous arrays are
allowed, f18 treats them as single-element arrays that are trivially
contiguous. This patch documents this semantic extension and
also adds comments to the predicate that implements the concept.
Differential Revision: https://reviews.llvm.org/D111679
To get proper wrap-around behavior for the various kind parameter
values of the optional COUNT= and COUNT_MAX= dummy arguments to
the intrinsic subroutine SYSTEM_CLOCK, add an extra argument to
the APIs for lowering to pass the integer kind of the actual argument.
Avoid confusion by requiring that both actual arguments have the same
kind when both are present. The results of the runtime functions
remain std::int64_t and lowering should still convert them before
storing to the actual argument variables.
Rework the implementation a bit to accomodate the dynamic
specification of the kind parameter, and to clean up some coding
issues with preprocessing and templates.
Use the kind of the COUNT=/COUNT_MAX= actual arguments to determine
the clock's resolution, where possible, in conformance with other
Fortran implementations.
Differential Revision: https://reviews.llvm.org/D111281
Add explicit documentation for a couple of cases where the Fortran
standard has been observed to be ambiguous or nonspecific and we've
had to choose the behavior of the implementation from some possible
alternatives (and may be distinct from other implementations).
Differential Revision: https://reviews.llvm.org/D111446
Support the extension intrinsic subroutines EXIT([status]) and ABORT()
in the intrinsic table and runtime support library. Lowering remains
to be done.
Differential Revision: https://reviews.llvm.org/D110741
Added 'this_image()' to the list of functions that are evaluated as intrinsic.
Added IsCoarray functions to determine if an expression is a coarray (corank > 1).
Added save attribute to coarray variables in test file, this_image.f90.
reviewers: klausler, PeteSteinfeld
Differential Revision: https://reviews.llvm.org/D108059
This reverts commit 81f8ad1769.
This seems to break the shared libs build
(linaro-flang-aarch64-sharedlibs bot) with:
undefined reference to `Fortran::semantics::IsCoarray(Fortran::semantics::Symbol const&)
(from tools/flang/lib/Evaluate/CMakeFiles/obj.FortranEvaluate.dir/tools.cpp.o)
When linking lib/libFortranEvaluate.so.14git
Added 'this_image()' to the list of functions that are evaluated as intrinsic.
Added IsCoarray functions to determine if an expression is a coarray (corank > 1).
Added save attribute to coarray variables in test file, this_image.f90.
reviewers: klausler, PeteSteinfeld
Differential Revision: https://reviews.llvm.org/D108059
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
This patch removes `f18`, a.k.a. the old driver. It is being replaced
with the new driver, `flang-new`, which has reached feature parity with
`f18` a while ago. This was discussed in [1] and also in [2].
With this change, `FLANG_BUILD_NEW_DRIVER` is no longer needed and is
also deleted. This means that we are making the dependency on Clang permanent
(i.e. it cannot be disabled with a CMake flag).
LIT set-up is updated accordingly. All references to `f18` or `f18.cpp`
are either updated or removed.
The `F18_FC` variable from the `flang` bash script is replaced with
`FLANG_FC`. The former is still supported for backwards compatibility.
[1] https://lists.llvm.org/pipermail/flang-dev/2021-June/000742.html
[2] https://reviews.llvm.org/D103177
Differential Revision: https://reviews.llvm.org/D105811
Like the similar legacy extension FLOAT(), DFLOAT() represents a
conversion from default integer to DOUBLE PRECISION. Rewrite
into a conversion operation.
Differential Revision: https://reviews.llvm.org/D107489
When a WRITE overwrites an endfile record, we need to forget
that there was an endfile record. When doing a BACKSPACE
after an explicit ENDFILE statement, the position afterwards
must be upon the endfile record.
Attempts to join list-directed delimited character input across
record boundaries was due to a bad reading of the standard
and has been deleted, now that the requirements are better understood.
This problem would cause a read attempt past EOF if a delimited
character input value was at the end of a record.
It turns out that delimited list-directed (and NAMELIST) character
output is required to emit contiguous doubled instances of the
delimiter character when it appears in the output value. When
fixed-size records are being emitted, as is the case with internal
output, this is not possible when the problematic character falls
on the last position of a record. No two other Fortran compilers
do the same thing in this situation so there is no good precedent
to follow.
Because it seems least wrong, with this patch we now emit one copy
of the delimiter as the last character of the current record and
another as the first character of the next record. (The
second-least-wrong alternative might be to flag a runtime error,
but that seems harsh since it's not an explicit error in the standard,
and the output may not have to be usable later as input anyway.)
Consequently, the output is not suitable for use as list-directed or
NAMELIST input.
If a later standard were to clarify this case, this behavior will of
course change as needed to conform.
Differential Revision: https://reviews.llvm.org/D106695
Use derived type information tables to drive default component
initialization (when needed), component destruction, and calls to
final subroutines. Perform these operations automatically for
ALLOCATE()/DEALLOCATE() APIs for allocatables, automatics, and
pointers. Add APIs for use in lowering to perform these operations
for non-allocatable/automatic non-pointer variables.
Data pointer component initialization supports arbitrary constant
designators, a F'2008 feature, which may be a first for Fortran
implementations.
Differential Revision: https://reviews.llvm.org/D106297
Flang diverges from the llvm coding style in that it requires braces
around the bodies of if/while/etc statements, even when the body is
a single statement.
This commit adds the readability-braces-around-statements check to
flang's clang-tidy config file. Hopefully the premerge bots will pick it
up and report violations in Phabricator.
We also explicitly disable the check in the directories corresponding to
the Lower and Optimizer libraries, which rely heavily on mlir and llvm
and therefore follow their coding style. Likewise for the tools
directory.
We also fix any outstanding violations in the runtime and in
lib/Semantics.
Differential Revision: https://reviews.llvm.org/D104100
As a benign extension common to other Fortran compilers,
accept BOZ literals in array constructors w/o explicit
types, treating them as integers.
Differential Revision: https://reviews.llvm.org/D103569
Describes how to run the Fortran LLVM Test Suite, specifically the external SPEC CPU 2017 Fortran tests.
Reviewed By: rovka
Differential Revision: https://reviews.llvm.org/D102877
Most Fortran compilers accept the following benign extension,
and it appears in some applications:
SUBROUTINE FOO(A,N)
IMPLICIT NONE
REAL A(N) ! N is used before being typed
INTEGER N
END
Allow it in f18 only for default integer scalar dummy arguments.
Differential Revesion: https://reviews.llvm.org/D96982
Fortran 2018 explicitly permits an ignored type declaration
for the result of a generic intrinsic function. See the comment
added to Semantics/expression.cpp for an explanation of why this
is somewhat dangerous and worthy of a warning.
Differential Revision: https://reviews.llvm.org/D96879
Now that semantics is working, the standard -fsyntax-only option of
GNU and Clang should be used as the name of the option that causes
f18 to just run the front-end. Support both options in f18, silently
accepting the old option as a synonym for the new one (as
preferred by the code owner), and replace all instances of the
old -fparse-only option with -fsyntax-only throughout the source base.
Differential Revision: https://reviews.llvm.org/D95887
Legacy Fortran implementations support an alternative form of the
PARAMETER statement; it differs syntactically from the standard's
PARAMETER statement by lacking parentheses, and semantically by
using the type and shape of the initialization expression to define
the attributes of the named constant. (GNU Fortran gets that part
wrong; Intel Fortran and nvfortran have full support.)
This patch disables the old style PARAMETER statement by default, as
it is syntactically ambiguous with conforming assignment statements;
adds a new "-falternative-parameter-statement" option to enable it;
and implements it correctly when enabled.
Fixes https://bugs.llvm.org/show_bug.cgi?id=48774, in which a user
tripped over the syntactic ambiguity.
Differential Revision: https://reviews.llvm.org/D95697
- updated the link to join the meeting to reflect the new WebEx information
- Added a note about the new Google Doc for keeping track of notes, and who
to contact if you experience access issues with the document
- Left a reference to the minutes from previous meetings being available
through a search of the flang-dev mailing list
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D93770
STORAGE_SIZE() is a standard inquiry intrinsic (size in bits
of an array element of the same type as the argument); SIZEOF()
is a common extension that returns the size in bytes of its
argument; C_SIZEOF() is a renaming of SIZEOF() in module ISO_C_BINDING.
STORAGE_SIZE() and SIZEOF() are implemented via rewrites to
expressions; these expressions will be constant when the necessary
type parameters and bounds are also constant.
Code to calculate the sizes of types (with and without alignment)
was isolated into Evaluate/type.* and /characteristics.*.
Code in Semantics/compute-offsets.* to calculate sizes and alignments
of derived types' scopes was exposed so that it can be called at type
instantiation time (earlier than before) so that these inquiry intrinsics
could be called from specification expressions.
Differential Revision: https://reviews.llvm.org/D93322
Define Fortran derived types that describe the characteristics
of derived types, and instantiations of parameterized derived
types, that are of relevance to the runtime language support
library. Define a suite of corresponding C++ structure types
for the runtime library to use to interpret instances of the
descriptions.
Create instances of these description types in Semantics as
static initializers for compiler-created objects in the scopes
that define or instantiate user derived types.
Delete obsolete code from earlier attempts to package runtime
type information.
Differential Revision: https://reviews.llvm.org/D92802
This patch plugs many holes in static initializer semantics, improves error
messages for default initial values and other component properties in
parameterized derived type instantiations, and cleans up several small
issues noticed during development. We now do proper scalar expansion,
folding, and type, rank, and shape conformance checking for component
default initializers in derived types and PDT instantiations.
The initial values of named constants are now guaranteed to have been folded
when installed in the symbol table, and are no longer folded or
scalar-expanded at each use in expression folding. Semantics documentation
was extended with information about the various kinds of initializations
in Fortran and when each of them are processed in the compiler.
Some necessary concomitant changes have bulked this patch out a bit:
* contextual messages attachments, which are now produced for parameterized
derived type instantiations so that the user can figure out which
instance caused a problem with a component, have been added as part
of ContextualMessages, and their implementation was debugged
* several APIs in evaluate::characteristics was changed so that a FoldingContext
is passed as an argument rather than just its intrinsic procedure table;
this affected client call sites in many files
* new tools in Evaluate/check-expression.cpp to determine when an Expr
actually is a single constant value and to validate a non-pointer
variable initializer or object component default value
* shape conformance checking has additional arguments that control
whether scalar expansion is allowed
* several now-unused functions and data members noticed and removed
* several crashes and bogus errors exposed by testing this new code
were fixed
* a -fdebug-stack-trace option to enable LLVM's stack tracing on
a crash, which might be useful in the future
TL;DR: Initialization processing does more and takes place at the right
times for all of the various kinds of things that can be initialized.
Differential Review: https://reviews.llvm.org/D92783
Fortran defines "null-init" null pointer initializers as
being function references, syntactically, that have to resolve
to calls to the intrinsic function NULL() with no actual
arguments.
Differential revision: https://reviews.llvm.org/D91657
Following warning were seen with recommonmark(0.5.0) and sphinx(1.8.5).
`parser.py:75: UserWarning: Container node skipped: type=document warn("Container node skipped: type={0}".format(mdnode.t))`
The warnings are due to an issue in recommonmark's(a python package) older versions.
A better solution is to use the latest version of recommonmark(>=0.6.0) to avoid
these issue in the first place.
This patch fixes the warnings for older versions.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D91117
2 Bug fixes:
- Do not resolve procedure as intrinsic if they appeared in an
EXTERNAL attribute statement (one path was not considering this flag)
- Emit an error if a procedure resolved to be an intrinsic function
(resp. subroutine) is used as a subroutine (resp. function).
Lowering was attempted while the evaluate::Expression for the
call was missing without any errors.
1 behavior change:
- Do not implicitly resolve subroutines (resp. functions) as intrinsics
because their name is the name of an intrinsic function (resp.
subroutine). Add justification in documentation.
Reviewed By: klausler, tskeith
Differential Revision: https://reviews.llvm.org/D90049
peter klausler