Clean up references to SVN in in the GCC docs, redirecting to Git
documentation as appropriate.
Where references to "the source code repository" rather than a
specific VCS make sense, I have used them. You might, after
all, change VCSes again someday.
I have not modified either generated HTML files nor maintainer scripts.
These changes should be complete with repect to the documentation tree.
2020-01-19 Eric S. Raymond <esr@thyrsus.com>
gcc/
* doc/contribute.texi: Update for SVN -> Git transition.
* doc/install.texi: Likewise.
libstdc++-v3
* doc/xml/faq.xml: Update for SVN -> Git transition.
* doc/xml/manual/appendix_contributing.xml: Likewise.
* doc/xml/manual/status_cxx1998.xml: Likewise.
* doc/xml/manual/status_cxx2011.xml: Likewise.
* doc/xml/manual/status_cxx2014.xml: Likewise.
* doc/xml/manual/status_cxx2017.xml: Likewise.
* doc/xml/manual/status_cxx2020.xml: Likewise.
* doc/xml/manual/status_cxxtr1.xml: Likewise.
* doc/xml/manual/status_cxxtr24733.xml: Likewise.
This is the squashed version of the first 6 patches that were split to
facilitate review.
The changes to libiberty (7th patch) to support demangling the co_await
operator stand alone and are applied separately.
The patch series is an initial implementation of a coroutine feature,
expected to be standardised in C++20.
Standardisation status (and potential impact on this implementation)
--------------------------------------------------------------------
The facility was accepted into the working draft for C++20 by WG21 in
February 2019. During following WG21 meetings, design and national body
comments have been reviewed, with no significant change resulting.
The current GCC implementation is against n4835 [1].
At this stage, the remaining potential for change comes from:
* Areas of national body comments that were not resolved in the version we
have worked to:
(a) handling of the situation where aligned allocation is available.
(b) handling of the situation where a user wants coroutines, but does not
want exceptions (e.g. a GPU).
* Agreed changes that have not yet been worded in a draft standard that we
have worked to.
It is not expected that the resolution to these can produce any major
change at this phase of the standardisation process. Such changes should be
limited to the coroutine-specific code.
ABI
---
The various compiler developers 'vendors' have discussed a minimal ABI to
allow one implementation to call coroutines compiled by another.
This amounts to:
1. The layout of a public portion of the coroutine frame.
Coroutines need to preserve state across suspension points, the storage for
this is called a "coroutine frame".
The ABI mandates that pointers into the coroutine frame point to an area
begining with two function pointers (to the resume and destroy functions
described below); these are immediately followed by the "promise object"
described in the standard.
This is sufficient that the builtins can take a coroutine frame pointer and
determine the address of the promise (or call the resume/destroy functions).
2. A number of compiler builtins that the standard library might use.
These are implemented by this patch series.
3. This introduces a new operator 'co_await' the mangling for which is also
agreed between vendors (and has an issue filed for that against the upstream
c++abi). Demangling for this is added to libiberty in a separate patch.
The ABI has currently no target-specific content (a given psABI might elect
to mandate alignment, but the common ABI does not do this).
Standard Library impact
-----------------------
The current implementations require addition of only a single header to
the standard library (no change to the runtime). This header is part of
the patch.
GCC Implementation outline
--------------------------
The standard's design for coroutines does not decorate the definition of
a coroutine in any way, so that a function is only known to be a coroutine
when one of the keywords (co_await, co_yield, co_return) is encountered.
This means that we cannot special-case such functions from the outset, but
must process them differently when they are finalised - which we do from
"finish_function ()".
At a high level, this design of coroutine produces four pieces from the
original user's function:
1. A coroutine state frame (taking the logical place of the activation
record for a regular function). One item stored in that state is the
index of the current suspend point.
2. A "ramp" function
This is what the user calls to construct the coroutine frame and start
the coroutine execution. This will return some object representing the
coroutine's eventual return value (or means to continue it when it it
suspended).
3. A "resume" function.
This is what gets called when a the coroutine is resumed when suspended.
4. A "destroy" function.
This is what gets called when the coroutine state should be destroyed
and its memory released.
The standard's coroutines involve cooperation of the user's authored function
with a provided "promise" class, which includes mandatory methods for
handling the state transitions and providing output values. Most realistic
coroutines will also have one or more 'awaiter' classes that implement the
user's actions for each suspend point. As we parse (or during template
expansion) the types of the promise and awaiter classes become known, and can
then be verified against the signatures expected by the standard.
Once the function is parsed (and templates expanded) we are able to make the
transformation into the four pieces noted above.
The implementation here takes the approach of a series of AST transforms.
The state machine suspend points are encoded in three internal functions
(one of which represents an exit from scope without cleanups). These three
IFNs are lowered early in the middle end, such that the majority of GCC's
optimisers can be run on the resulting output.
As a design choice, we have carried out the outlining of the user's function
in the front end, and taken advantage of the existing middle end's abilities
to inline and DCE where that is profitable.
Since the state machine is actually common to both resumer and destroyer
functions, we make only a single function "actor" that contains both the
resume and destroy paths. The destroy function is represented by a small
stub that sets a value to signal the use of the destroy path and calls the
actor. The idea is that optimisation of the state machine need only be done
once - and then the resume and destroy paths can be identified allowing the
middle end's inline and DCE machinery to optimise as profitable as noted
above.
The middle end components for this implementation are:
A pass that:
1. Lowers the coroutine builtins that allow the standard library header to
interact with the coroutine frame (these fairly simple logical or
numerical substitution of values, given a coroutine frame pointer).
2. Lowers the IFN that represents the exit from state without cleanup.
Essentially, this becomes a gimple goto.
3. Sets the final size of the coroutine frame at this stage.
A second pass (that requires the revised CFG that results from the lowering
of the scope exit IFNs in the first).
1. Lower the IFNs that represent the state machine paths for the resume and
destroy cases.
Patches squashed into this commit:
[C++ coroutines 1] Common code and base definitions.
This part of the patch series provides the gating flag, the keywords,
cpp defines etc.
[C++ coroutines 2] Define builtins and internal functions.
This part of the patch series provides the builtin functions
used by the standard library code and the internal functions
used to implement lowering of the coroutine state machine.
[C++ coroutines 3] Front end parsing and transforms.
There are two parts to this.
1. Parsing, template instantiation and diagnostics for the standard-
mandated class entries.
The user authors a function that becomes a coroutine (lazily) by
making use of any of the co_await, co_yield or co_return keywords.
Unlike a regular function, where the activation record is placed on the
stack, and is destroyed on function exit, a coroutine has some state that
persists between calls - the 'coroutine frame' (thus analogous to a stack
frame).
We transform the user's function into three pieces:
1. A so-called ramp function, that establishes the coroutine frame and
begins execution of the coroutine.
2. An actor function that contains the state machine corresponding to the
user's suspend/resume structure.
3. A stub function that calls the actor function in 'destroy' mode.
The actor function is executed:
* from "resume point 0" by the ramp.
* from resume point N ( > 0 ) for handle.resume() calls.
* from the destroy stub for destroy point N for handle.destroy() calls.
The C++ coroutine design described in the standard makes use of some helper
methods that are authored in a so-called "promise" class provided by the
user.
At parse time (or post substitution) the type of the coroutine promise
will be determined. At that point, we can look up the required promise
class methods and issue diagnostics if they are missing or incorrect. To
avoid repeating these actions at code-gen time, we make use of temporary
'proxy' variables for the coroutine handle and the promise - which will
eventually be instantiated in the coroutine frame.
Each of the keywords will expand to a code sequence (although co_yield is
just syntactic sugar for a co_await).
We defer the analysis and transformatin until template expansion is
complete so that we have complete types at that time.
2. AST analysis and transformation which performs the code-gen for the
outlined state machine.
The entry point here is morph_fn_to_coro () which is called from
finish_function () when we have completed any template expansion.
This is preceded by helper functions that implement the phases below.
The process proceeds in four phases.
A Initial framing.
The user's function body is wrapped in the initial and final suspend
points and we begin building the coroutine frame.
We build empty decls for the actor and destroyer functions at this
time too.
When exceptions are enabled, the user's function body will also be
wrapped in a try-catch block with the catch invoking the promise
class 'unhandled_exception' method.
B Analysis.
The user's function body is analysed to determine the suspend points,
if any, and to capture local variables that might persist across such
suspensions. In most cases, it is not necessary to capture compiler
temporaries, since the tree-lowering nests the suspensions correctly.
However, in the case of a captured reference, there is a lifetime
extension to the end of the full expression - which can mean across a
suspend point in which case it must be promoted to a frame variable.
At the conclusion of analysis, we have a conservative frame layout and
maps of the local variables to their frame entry points.
C Build the ramp function.
Carry out the allocation for the coroutine frame (NOTE; the actual size
computation is deferred until late in the middle end to allow for future
optimisations that will be allowed to elide unused frame entries).
We build the return object.
D Build and expand the actor and destroyer function bodies.
The destroyer is a trivial shim that sets a bit to indicate that the
destroy dispatcher should be used and then calls into the actor.
The actor function is the implementation of the user's state machine.
The current suspend point is noted in an index.
Each suspend point is encoded as a pair of internal functions, one in
the relevant dispatcher, and one representing the suspend point.
During this process, the user's local variables and the proxies for the
self-handle and the promise class instanceare re-written to their
coroutine frame equivalents.
The complete bodies for the ramp, actor and destroy function are passed
back to finish_function for folding and gimplification.
[C++ coroutines 4] Middle end expanders and transforms.
The first part of this is a pass that provides:
* expansion of the library support builtins, these are simple boolean
or numerical substitutions.
* The functionality of implementing an exit from scope without cleanup
is performed here by lowering an IFN to a gimple goto.
This pass has to run for non-coroutine functions, since functions calling
the builtins are not necessarily coroutines (i.e. they are implementing the
library interfaces which may be called from anywhere).
The second part is the expansion of the coroutine IFNs that describe the
state machine connections to the dispatchers. This only has to be run
for functions that are coroutine components. The work done by this pass
is:
In the front end we construct a single actor function that contains
the coroutine state machine.
The actor function has three entry conditions:
1. from the ramp, resume point 0 - to initial-suspend.
2. when resume () is executed (resume point N).
3. from the destroy () shim when that is executed.
The actor function begins with two dispatchers; one for resume and
one for destroy (where the initial entry from the ramp is a special-
case of resume point 0).
Each suspend point and each dispatch entry is marked with an IFN such
that we can connect the relevant dispatchers to their target labels.
So, if we have:
CO_YIELD (NUM, FINAL, RES_LAB, DEST_LAB, FRAME_PTR)
This is await point NUM, and is the final await if FINAL is non-zero.
The resume point is RES_LAB, and the destroy point is DEST_LAB.
We expect to find a CO_ACTOR (NUM) in the resume dispatcher and a
CO_ACTOR (NUM+1) in the destroy dispatcher.
Initially, the intent of keeping the resume and destroy paths together
is that the conditionals controlling them are identical, and thus there
would be duplication of any optimisation of those paths if the split
were earlier.
Subsequent inlining of the actor (and DCE) is then able to extract the
resume and destroy paths as separate functions if that is found
profitable by the optimisers.
Once we have remade the connections to their correct postions, we elide
the labels that the front end inserted.
[C++ coroutines 5] Standard library header.
This provides the interfaces mandated by the standard and implements
the interaction with the coroutine frame by means of inline use of
builtins expanded at compile-time. There should be a 1:1 correspondence
with the standard sections which are cross-referenced.
There is no runtime content.
At this stage, we have the content in an inline namespace "__n4835" for
the CD we worked to.
[C++ coroutines 6] Testsuite.
There are two categories of test:
1. Checks for correctly formed source code and the error reporting.
2. Checks for transformation and code-gen.
The second set are run as 'torture' tests for the standard options
set, including LTO. These are also intentionally run with no options
provided (from the coroutines.exp script).
gcc/ChangeLog:
2020-01-18 Iain Sandoe <iain@sandoe.co.uk>
* Makefile.in: Add coroutine-passes.o.
* builtin-types.def (BT_CONST_SIZE): New.
(BT_FN_BOOL_PTR): New.
(BT_FN_PTR_PTR_CONST_SIZE_BOOL): New.
* builtins.def (DEF_COROUTINE_BUILTIN): New.
* coroutine-builtins.def: New file.
* coroutine-passes.cc: New file.
* function.h (struct GTY function): Add a bit to indicate that the
function is a coroutine component.
* internal-fn.c (expand_CO_FRAME): New.
(expand_CO_YIELD): New.
(expand_CO_SUSPN): New.
(expand_CO_ACTOR): New.
* internal-fn.def (CO_ACTOR): New.
(CO_YIELD): New.
(CO_SUSPN): New.
(CO_FRAME): New.
* passes.def: Add pass_coroutine_lower_builtins,
pass_coroutine_early_expand_ifns.
* tree-pass.h (make_pass_coroutine_lower_builtins): New.
(make_pass_coroutine_early_expand_ifns): New.
* doc/invoke.texi: Document the fcoroutines command line
switch.
gcc/c-family/ChangeLog:
2020-01-18 Iain Sandoe <iain@sandoe.co.uk>
* c-common.c (co_await, co_yield, co_return): New.
* c-common.h (RID_CO_AWAIT, RID_CO_YIELD,
RID_CO_RETURN): New enumeration values.
(D_CXX_COROUTINES): Bit to identify coroutines are active.
(D_CXX_COROUTINES_FLAGS): Guard for coroutine keywords.
* c-cppbuiltin.c (__cpp_coroutines): New cpp define.
* c.opt (fcoroutines): New command-line switch.
gcc/cp/ChangeLog:
2020-01-18 Iain Sandoe <iain@sandoe.co.uk>
* Make-lang.in: Add coroutines.o.
* cp-tree.h (lang_decl-fn): coroutine_p, new bit.
(DECL_COROUTINE_P): New.
* lex.c (init_reswords): Enable keywords when the coroutine flag
is set,
* operators.def (co_await): New operator.
* call.c (add_builtin_candidates): Handle CO_AWAIT_EXPR.
(op_error): Likewise.
(build_new_op_1): Likewise.
(build_new_function_call): Validate coroutine builtin arguments.
* constexpr.c (potential_constant_expression_1): Handle
CO_AWAIT_EXPR, CO_YIELD_EXPR, CO_RETURN_EXPR.
* coroutines.cc: New file.
* cp-objcp-common.c (cp_common_init_ts): Add CO_AWAIT_EXPR,
CO_YIELD_EXPR, CO_RETRN_EXPR as TS expressions.
* cp-tree.def (CO_AWAIT_EXPR, CO_YIELD_EXPR, (CO_RETURN_EXPR): New.
* cp-tree.h (coro_validate_builtin_call): New.
* decl.c (emit_coro_helper): New.
(finish_function): Handle the case when a function is found to
be a coroutine, perform the outlining and emit the outlined
functions. Set a bit to signal that this is a coroutine component.
* parser.c (enum required_token): New enumeration RT_CO_YIELD.
(cp_parser_unary_expression): Handle co_await.
(cp_parser_assignment_expression): Handle co_yield.
(cp_parser_statement): Handle RID_CO_RETURN.
(cp_parser_jump_statement): Handle co_return.
(cp_parser_operator): Handle co_await operator.
(cp_parser_yield_expression): New.
(cp_parser_required_error): Handle RT_CO_YIELD.
* pt.c (tsubst_copy): Handle CO_AWAIT_EXPR.
(tsubst_expr): Handle CO_AWAIT_EXPR, CO_YIELD_EXPR and
CO_RETURN_EXPRs.
* tree.c (cp_walk_subtrees): Likewise.
libstdc++-v3/ChangeLog:
2020-01-18 Iain Sandoe <iain@sandoe.co.uk>
* include/Makefile.am: Add coroutine to the std set.
* include/Makefile.in: Regenerated.
* include/std/coroutine: New file.
gcc/testsuite/ChangeLog:
2020-01-18 Iain Sandoe <iain@sandoe.co.uk>
* g++.dg/coroutines/co-await-syntax-00-needs-expr.C: New test.
* g++.dg/coroutines/co-await-syntax-01-outside-fn.C: New test.
* g++.dg/coroutines/co-await-syntax-02-outside-fn.C: New test.
* g++.dg/coroutines/co-await-syntax-03-auto.C: New test.
* g++.dg/coroutines/co-await-syntax-04-ctor-dtor.C: New test.
* g++.dg/coroutines/co-await-syntax-05-constexpr.C: New test.
* g++.dg/coroutines/co-await-syntax-06-main.C: New test.
* g++.dg/coroutines/co-await-syntax-07-varargs.C: New test.
* g++.dg/coroutines/co-await-syntax-08-lambda-auto.C: New test.
* g++.dg/coroutines/co-return-syntax-01-outside-fn.C: New test.
* g++.dg/coroutines/co-return-syntax-02-outside-fn.C: New test.
* g++.dg/coroutines/co-return-syntax-03-auto.C: New test.
* g++.dg/coroutines/co-return-syntax-04-ctor-dtor.C: New test.
* g++.dg/coroutines/co-return-syntax-05-constexpr-fn.C: New test.
* g++.dg/coroutines/co-return-syntax-06-main.C: New test.
* g++.dg/coroutines/co-return-syntax-07-vararg.C: New test.
* g++.dg/coroutines/co-return-syntax-08-bad-return.C: New test.
* g++.dg/coroutines/co-return-syntax-09-lambda-auto.C: New test.
* g++.dg/coroutines/co-yield-syntax-00-needs-expr.C: New test.
* g++.dg/coroutines/co-yield-syntax-01-outside-fn.C: New test.
* g++.dg/coroutines/co-yield-syntax-02-outside-fn.C: New test.
* g++.dg/coroutines/co-yield-syntax-03-auto.C: New test.
* g++.dg/coroutines/co-yield-syntax-04-ctor-dtor.C: New test.
* g++.dg/coroutines/co-yield-syntax-05-constexpr.C: New test.
* g++.dg/coroutines/co-yield-syntax-06-main.C: New test.
* g++.dg/coroutines/co-yield-syntax-07-varargs.C: New test.
* g++.dg/coroutines/co-yield-syntax-08-needs-expr.C: New test.
* g++.dg/coroutines/co-yield-syntax-09-lambda-auto.C: New test.
* g++.dg/coroutines/coro-builtins.C: New test.
* g++.dg/coroutines/coro-missing-gro.C: New test.
* g++.dg/coroutines/coro-missing-promise-yield.C: New test.
* g++.dg/coroutines/coro-missing-ret-value.C: New test.
* g++.dg/coroutines/coro-missing-ret-void.C: New test.
* g++.dg/coroutines/coro-missing-ueh-1.C: New test.
* g++.dg/coroutines/coro-missing-ueh-2.C: New test.
* g++.dg/coroutines/coro-missing-ueh-3.C: New test.
* g++.dg/coroutines/coro-missing-ueh.h: New test.
* g++.dg/coroutines/coro-pre-proc.C: New test.
* g++.dg/coroutines/coro.h: New file.
* g++.dg/coroutines/coro1-ret-int-yield-int.h: New file.
* g++.dg/coroutines/coroutines.exp: New file.
* g++.dg/coroutines/torture/alloc-00-gro-on-alloc-fail.C: New test.
* g++.dg/coroutines/torture/alloc-01-overload-newdel.C: New test.
* g++.dg/coroutines/torture/call-00-co-aw-arg.C: New test.
* g++.dg/coroutines/torture/call-01-multiple-co-aw.C: New test.
* g++.dg/coroutines/torture/call-02-temp-co-aw.C: New test.
* g++.dg/coroutines/torture/call-03-temp-ref-co-aw.C: New test.
* g++.dg/coroutines/torture/class-00-co-ret.C: New test.
* g++.dg/coroutines/torture/class-01-co-ret-parm.C: New test.
* g++.dg/coroutines/torture/class-02-templ-parm.C: New test.
* g++.dg/coroutines/torture/class-03-operator-templ-parm.C: New test.
* g++.dg/coroutines/torture/class-04-lambda-1.C: New test.
* g++.dg/coroutines/torture/class-05-lambda-capture-copy-local.C: New test.
* g++.dg/coroutines/torture/class-06-lambda-capture-ref.C: New test.
* g++.dg/coroutines/torture/co-await-00-trivial.C: New test.
* g++.dg/coroutines/torture/co-await-01-with-value.C: New test.
* g++.dg/coroutines/torture/co-await-02-xform.C: New test.
* g++.dg/coroutines/torture/co-await-03-rhs-op.C: New test.
* g++.dg/coroutines/torture/co-await-04-control-flow.C: New test.
* g++.dg/coroutines/torture/co-await-05-loop.C: New test.
* g++.dg/coroutines/torture/co-await-06-ovl.C: New test.
* g++.dg/coroutines/torture/co-await-07-tmpl.C: New test.
* g++.dg/coroutines/torture/co-await-08-cascade.C: New test.
* g++.dg/coroutines/torture/co-await-09-pair.C: New test.
* g++.dg/coroutines/torture/co-await-10-template-fn-arg.C: New test.
* g++.dg/coroutines/torture/co-await-11-forwarding.C: New test.
* g++.dg/coroutines/torture/co-await-12-operator-2.C: New test.
* g++.dg/coroutines/torture/co-await-13-return-ref.C: New test.
* g++.dg/coroutines/torture/co-ret-00-void-return-is-ready.C: New test.
* g++.dg/coroutines/torture/co-ret-01-void-return-is-suspend.C: New test.
* g++.dg/coroutines/torture/co-ret-03-different-GRO-type.C: New test.
* g++.dg/coroutines/torture/co-ret-04-GRO-nontriv.C: New test.
* g++.dg/coroutines/torture/co-ret-05-return-value.C: New test.
* g++.dg/coroutines/torture/co-ret-06-template-promise-val-1.C: New test.
* g++.dg/coroutines/torture/co-ret-07-void-cast-expr.C: New test.
* g++.dg/coroutines/torture/co-ret-08-template-cast-ret.C: New test.
* g++.dg/coroutines/torture/co-ret-09-bool-await-susp.C: New test.
* g++.dg/coroutines/torture/co-ret-10-expression-evaluates-once.C: New test.
* g++.dg/coroutines/torture/co-ret-11-co-ret-co-await.C: New test.
* g++.dg/coroutines/torture/co-ret-12-co-ret-fun-co-await.C: New test.
* g++.dg/coroutines/torture/co-ret-13-template-2.C: New test.
* g++.dg/coroutines/torture/co-ret-14-template-3.C: New test.
* g++.dg/coroutines/torture/co-yield-00-triv.C: New test.
* g++.dg/coroutines/torture/co-yield-01-multi.C: New test.
* g++.dg/coroutines/torture/co-yield-02-loop.C: New test.
* g++.dg/coroutines/torture/co-yield-03-tmpl.C: New test.
* g++.dg/coroutines/torture/co-yield-04-complex-local-state.C: New test.
* g++.dg/coroutines/torture/co-yield-05-co-aw.C: New test.
* g++.dg/coroutines/torture/co-yield-06-fun-parm.C: New test.
* g++.dg/coroutines/torture/co-yield-07-template-fn-param.C: New test.
* g++.dg/coroutines/torture/co-yield-08-more-refs.C: New test.
* g++.dg/coroutines/torture/co-yield-09-more-templ-refs.C: New test.
* g++.dg/coroutines/torture/coro-torture.exp: New file.
* g++.dg/coroutines/torture/exceptions-test-0.C: New test.
* g++.dg/coroutines/torture/func-params-00.C: New test.
* g++.dg/coroutines/torture/func-params-01.C: New test.
* g++.dg/coroutines/torture/func-params-02.C: New test.
* g++.dg/coroutines/torture/func-params-03.C: New test.
* g++.dg/coroutines/torture/func-params-04.C: New test.
* g++.dg/coroutines/torture/func-params-05.C: New test.
* g++.dg/coroutines/torture/func-params-06.C: New test.
* g++.dg/coroutines/torture/lambda-00-co-ret.C: New test.
* g++.dg/coroutines/torture/lambda-01-co-ret-parm.C: New test.
* g++.dg/coroutines/torture/lambda-02-co-yield-values.C: New test.
* g++.dg/coroutines/torture/lambda-03-auto-parm-1.C: New test.
* g++.dg/coroutines/torture/lambda-04-templ-parm.C: New test.
* g++.dg/coroutines/torture/lambda-05-capture-copy-local.C: New test.
* g++.dg/coroutines/torture/lambda-06-multi-capture.C: New test.
* g++.dg/coroutines/torture/lambda-07-multi-yield.C: New test.
* g++.dg/coroutines/torture/lambda-08-co-ret-parm-ref.C: New test.
* g++.dg/coroutines/torture/local-var-0.C: New test.
* g++.dg/coroutines/torture/local-var-1.C: New test.
* g++.dg/coroutines/torture/local-var-2.C: New test.
* g++.dg/coroutines/torture/local-var-3.C: New test.
* g++.dg/coroutines/torture/local-var-4.C: New test.
* g++.dg/coroutines/torture/mid-suspend-destruction-0.C: New test.
* g++.dg/coroutines/torture/pr92933.C: New test.
In a freestanding library we don't install the <pstl/pstl_config.h>
header, so don't try to include it unless it exists.
Explicitly declare aligned alloc functions for freestanding, because
<cstdlib> doesn't declare them.
PR libstdc++/92376
* include/bits/c++config: Only do PSTL config when the header is
present, to fix freestanding.
* libsupc++/new_opa.cc [!_GLIBCXX_HOSTED]: Declare allocation
functions if they were detected by configure.
This removes support for EOL versions of NetBSD and syncs the
definitions with patches from NetBSD upstream.
The only change here that isn't from upstream is to use _CTYPE_BL for
the isblank class, which is correct but wasn't previously done either in
FSF GCC or the NetBSD packages.
2020-01-16 Kai-Uwe Eckhardt <kuehro@gmx.de>
Matthew Bauer <mjbauer95@gmail.com>
Jonathan Wakely <jwakely@redhat.com>
PR bootstrap/64271 (partial)
* config/os/bsd/netbsd/ctype_base.h (ctype_base::mask): Change type
to unsigned short.
(ctype_base::alpha, ctype_base::digit, ctype_base::xdigit)
(ctype_base::print, ctype_base::graph, ctype_base::alnum): Sync
definitions with NetBSD upstream.
(ctype_base::blank): Use _CTYPE_BL.
* config/os/bsd/netbsd/ctype_configure_char.cc (_C_ctype_): Remove
Declaration.
(ctype<char>::classic_table): Use _C_ctype_tab_ instead of _C_ctype_.
(ctype<char>::do_toupper, ctype<char>::do_tolower): Cast char
parameters to unsigned char.
* config/os/bsd/netbsd/ctype_inline.h (ctype<char>::is): Likewise.
Avoid comparing elements with operator== multiple times by replacing
uses of find and equal_range with equivalent inlined code that uses
operator== instead of the container's equality comparison predicate.
This is valid because the standard requires that operator== is a
refinement of the equality predicate.
Also replace the _S_is_permutation function with std::is_permutation,
which wasn't yet implemented when this code was first written.
PR libstdc++/91263
* include/bits/hashtable.h (_Hashtable<>): Make _Equality<> friend.
* include/bits/hashtable_policy.h: Include <bits/stl_algo.h>.
(_Equality_base): Remove.
(_Equality<>::_M_equal): Review implementation. Use
std::is_permutation.
* testsuite/23_containers/unordered_multiset/operators/1.cc
(Hash, Equal, test02, test03): New.
* testsuite/23_containers/unordered_set/operators/1.cc
(Hash, Equal, test02, test03): New.
The __iota_diff_t alias can be the type __int128, but that does not
satisfy the signed_integral and __is_signed_integer_like concepts when
__STRICT_ANSI__ is defined (which is true for -std=c++2a).
Because weakly_incrementable is defined in terms of signed_integral, it
is not satisfied by __int128, which means iota_view's iterator doesn't
always satisfy input_or_output_iterator and so iota_view is not always a
range.
The solution is to define __max_size_type and __max_diff_type using
__int128, so that __is_signed_integer_like allows __int128, and then
make weakly_incrementable use __is_signed_integer_like instead of
signed_integral.
PR libstdc++/93267
* include/bits/iterator_concepts.h (__max_diff_type, __max_size_type):
Move here from <bits/range_access.h> and define using __int128 when
available.
(__is_integer_like, __is_signed_integer_like): Move here from
<bits/range_access.h>.
(weakly_incrementable): Use __is_signed_integer_like.
* include/bits/range_access.h (__max_diff_type, __max_size_type)
(__is_integer_like, __is_signed_integer_like): Move to
<bits/iterator_concepts.h>.
(__make_unsigned_like_t): Move here from <ranges>.
* include/std/ranges (__make_unsigned_like_t): Move to
<bits/range_access.h>.
(iota_view): Replace using-directive with using-declarations.
* testsuite/std/ranges/iota/93267.cc: New test.
* testsuite/std/ranges/iota_view.cc: Move to new 'iota' sub-directory.
PR libstdc++/93244
* include/bits/fs_path.h (path::generic_string<C,A>)
[_GLIBCXX_FILESYSTEM_IS_WINDOWS]: Convert root-dir to forward-slash.
* testsuite/27_io/filesystem/path/generic/generic_string.cc: Check
root-dir is converted to forward slash in generic pathname.
* testsuite/27_io/filesystem/path/generic/utf.cc: New test.
* testsuite/27_io/filesystem/path/generic/wchar_t.cc: New test.
This implements the new requirements for C++20 that std::atomic should
initialize the atomic variable in its default constructor.
This patch does not add the deprecated attribute to atomic_init, but
that should be done at some point as it's deprecated in C++20.
The paper also deprecates the ATOMIC_FLAG_INIT macro, although we can't
apply the deprecated attribute to a macro.
PR libstdc++/58605
* include/bits/atomic_base.h (__cpp_lib_atomic_value_initialization):
Define.
(__atomic_flag_base, __atomic_base, __atomic_base<_PTp*>)
(__atomic_float): Add default member initializer for C++20.
* include/std/atomic (atomic): Likewise.
(atomic::atomic()): Remove noexcept-specifier on default constructor.
* include/std/version (__cpp_lib_atomic_value_initialization): Define.
* testsuite/29_atomics/atomic/cons/assign_neg.cc: Adjust dg-error line
number.
* testsuite/29_atomics/atomic/cons/copy_neg.cc: Likewise.
* testsuite/29_atomics/atomic/cons/value_init.cc: New test.
* testsuite/29_atomics/atomic_flag/cons/value_init.cc: New test.
* testsuite/29_atomics/atomic_flag/requirements/trivial.cc: Adjust
expected result for is_trivially_default_constructible.
* testsuite/29_atomics/atomic_float/requirements.cc: Likewise.
* testsuite/29_atomics/atomic_float/value_init.cc: New test.
* testsuite/29_atomics/atomic_integral/cons/assign_neg.cc: Likewise.
* testsuite/29_atomics/atomic_integral/cons/copy_neg.cc: Likewise.
* testsuite/29_atomics/atomic_integral/cons/value_init.cc
* testsuite/29_atomics/atomic_integral/requirements/trivial.cc: Adjust
expected results for is_trivially_default_constructible.
* testsuite/util/testsuite_common_types.h (has_trivial_dtor): Add
new test generator.
This fixes a typo and also explains why test_container is not a range
when used with output_iterator_wrapper or input_iterator_wrapper.
* testsuite/util/testsuite_iterators.h: Improve comment.
From-SVN: r280146
Since LWG 445 was implemented for GCC 4.7, the std::iterator base class
of std::istreambuf_iterator changes type depending on the -std mode
used. This creates an ABI incompatibility between different -std modes.
This change ensures the base class always has the same type. This makes
layout for C++98 compatible with the current -std=gnu++14 default, but
no longer compatible with C++98 code from previous releases. In practice
this is unlikely to cause real problems, because it only affects the
layout of types with two std::iterator base classes, one of which comes
from std::istreambuf_iterator. Such types are expected to be vanishingly
rare.
PR libstdc++/92285
* include/bits/streambuf_iterator.h (istreambuf_iterator): Make type
of base class independent of __cplusplus value.
[__cplusplus < 201103L] (istreambuf_iterator::reference): Override the
type defined in the base class
* testsuite/24_iterators/istreambuf_iterator/92285.cc: New test.
* testsuite/24_iterators/istreambuf_iterator/requirements/
base_classes.cc: Adjust expected base class for C++98.
From-SVN: r280116
The equality operators for _ExtPtr_allocator are defined as non-const
member functions, which causes ambiguities in C++20 due to the
synthesized operator!= candidates. They should always have been const.
The _Pointer_adapter class template has both value_type and element_type
members, which makes readable_traits<_Pointer_adapter<T>> ambiguous. The
intended workaround is to add a specialization of readable_traits.
* include/ext/extptr_allocator.h (_ExtPtr_allocator::operator==)
(_ExtPtr_allocator::operator!=): Add missing const qualifiers.
* include/ext/pointer.h (readable_traits<_Pointer_adapter<S>>): Add
partial specialization to disambiguate the two constrained
specializations.
From-SVN: r280067
With -std=gnu++2a and -Wsystem-headers the std::is_pod deprecation
causes some new diagnostics. This suppresses them.
* include/experimental/type_traits (experimental::is_pod_v): Disable
-Wdeprecated-declarations warnings around reference to std::is_pod.
* include/std/type_traits (is_pod_v): Likewise.
* testsuite/18_support/max_align_t/requirements/2.cc: Also check
is_standard_layout and is_trivial. Do not check is_pod for C++20.
* testsuite/20_util/is_pod/requirements/explicit_instantiation.cc:
Add -Wno-deprecated for C++20.
* testsuite/20_util/is_pod/requirements/typedefs.cc: Likewise.
* testsuite/20_util/is_pod/value.cc: Likewise.
* testsuite/experimental/type_traits/value.cc: Likewise.
From-SVN: r280066
This adds the deprecated attribute to std::is_pod and std::is_pod_v for
C++20.
2019-12-05 JeanHeyd "ThePhD" Meneide <phdofthehouse@gmail.com>
* include/bits/c++config (_GLIBCXX20_DEPRECATED): Add new macro.
* include/std/type_traits (is_pod, is_pod_v): Deprecate for C++20.
* testuite/20_util/is_pod/deprecated-2a.cc: New test.
From-SVN: r280065
The deserialization functions for random number distributions fail to
check the stream state before using the extracted values. In some cases
this leads to using indeterminate values to resize a vector, and then
filling that vector with indeterminate values.
No values that affect control flow should be used without checking that a
good value was read from the stream.
Additionally, where reasonable to do so, defer modifying any state in
the distribution until all values have been successfully read, to avoid
modifying some of the distribution's parameters and leaving others
unchanged.
PR libstdc++/93205
* include/bits/random.h (operator>>): Check stream operation succeeds.
* include/bits/random.tcc (operator<<): Remove redundant __ostream_type
typedefs.
(operator>>): Remove redundant __istream_type typedefs. Check stream
operations succeed.
(__extract_params): New function to fill a vector from a stream.
* testsuite/26_numerics/random/pr60037-neg.cc: Adjust dg-error line.
From-SVN: r280061
This prevents the vtables and RTTI from being emitted in every object
file that uses memory_resource and monotonic_buffer_resource.
Objects compiled by GCC 9.1 or 9.2 will contain inline definitions of
the destructors, vtable and RTTI, but this is harmless. The inline
definitions have identical effects to the ones that are now defined in
libstdc++.so so it doesn't matter if the inline ones are used instead of
calling the symbols exported from the runtime library.
PR libstdc++/93208
* config/abi/pre/gnu.ver: Add new exports.
* include/std/memory_resource (memory_resource::~memory_resource()):
Do not define inline.
(monotonic_buffer_resource::~monotonic_buffer_resource()): Likewise.
* src/c++17/memory_resource.cc (memory_resource::~memory_resource()):
Define.
(monotonic_buffer_resource::~monotonic_buffer_resource()): Define.
* testsuite/20_util/monotonic_buffer_resource/93208.cc: New test.
From-SVN: r280044
When recursing into a directory, any errors that occur while removing a
directory entry are ignored, because the subsequent increment of the
directory iterator clears the error_code object.
This fixes that bug by checking the result of each recursive operation
before incrementing. This is a change in observable behaviour, because
previously other directory entries would still be removed even if one
(or more) couldn't be removed due to errors. Now the operation stops on
the first error, which is what the code intended to do all along. The
standard doesn't specify what happens in this case (because the order
that the entries are processed is unspecified anyway).
It also improves the error reporting so that the name of the file that
could not be removed is included in the filesystem_error exception. This
is done by introducing a new helper type for reporting errors with
additional context and a new function that uses that type. Then the
overload of std::filesystem::remove_all that throws an exception can use
the new function to ensure any exception contains the additional
information.
For std::experimental::filesystem::remove_all just fix the bug where
errors are ignored.
PR libstdc++/93201
* src/c++17/fs_ops.cc (do_remove_all): New function implementing more
detailed error reporting for remove_all. Check result of recursive
call before incrementing iterator.
(remove_all(const path&), remove_all(const path&, error_code&)): Use
do_remove_all.
* src/filesystem/ops.cc (remove_all(const path&, error_code&)): Check
result of recursive call before incrementing iterator.
* testsuite/27_io/filesystem/operations/remove_all.cc: Check errors
are reported correctly.
* testsuite/experimental/filesystem/operations/remove_all.cc: Likewise.
From-SVN: r280014
2020-01-07 Thomas Rodgers <trodgers@redhat.com>
* include/std/condition_variable
(condition_variable_any::wait_on): Rename to match current draft
standard.
(condition_variable_any::wait_on_until): Likewise.
(condition_variable_any::wait_on_for): Likewise.
* testsuite/30_threads/condition_variable_any/stop_token/wait_on.cc:
Adjust tests to account for renamed methods.
From-SVN: r279988
The contents of the <compare> header are not complete unless concepts
are supported, so the feature test macro should depend on the macro for
concepts.
As a result, the std::lexicographical_compare_three_way function will
not be defined unless concepts are supported, so there is no need to
check __cpp_lib_concepts before using concepts in those functions.
* include/bits/stl_algobase.h (__is_byte_iter, __min_cmp)
(lexicographical_compare_three_way): Do not depend on
__cpp_lib_concepts.
* include/std/version (__cpp_lib_three_way_comparison): Only define
when __cpp_lib_concepts is defined.
* libsupc++/compare (__cpp_lib_three_way_comparison): Likewise.
From-SVN: r279896
Clang now supports three-way comparisons. That causes both overloads of
std::lexicographical_compare_three_way to be defined, but the second one
uses std::compare_three_way which depends on concepts. Clang does not
yet support concepts, so the second overload should also depend on
__cpp_lib_concepts.
* include/bits/stl_algobase.h (lexicographical_compare_three_way):
Only define four-argument overload when __cpp_lib_concepts is defined.
From-SVN: r279861
This change reworks the VxWorks specific os_defines.h internal
lisbstdc++ header to help fix build and runtime failures of various
kinds in environments from 6.4/6.9 to 7 SR640, based on experiments
and observations conducted against real installs of these OSes for
different CPU architectures.
2019-12-30 Jerome Lambourg <lambourg@adacore.com>
Olivier Hainque <hainque@adacore.com>
libstdc++
* config/os/vxworks/os_defines.h
(NOMINMAX): Always redefine to 1.
(_NO_CPP_INLINES): Likewise.
(_GLIBCXX_USE_WEAK_REF): Define to 1 for RTP on
VxWorks >= 7, to 0 otherwise.
(_GLIBCXX_HAVE_TLS): Define to 1.
For VxWorks >= 7:
(_GLIBCXX_USE_C99_MATH): Define to 1.
(_GLIBCXX_USE_C99_MATH_FP_MACROS_DYNAMIC): Define to 0.
(_HAS_TR1_DECLARATIONS): Redefine to 0.
For VxWorks < 7, RTP:
(_GLIBCXX_INCLUDE_NEXT_C_HEADERS): Define to 1.
(_GLIBCXX_USE_C99_FP_MACROS_DYNAMIC): Redefine to 1.
(__CORRECT_ISO_CPP11_MATH_H_PROTO_FP): Define.
For VxWorks < 7, kernel: #include <vxWorks.h>
Co-Authored-By: Olivier Hainque <hainque@adacore.com>
From-SVN: r279792
When cross-building for vxworks, test for declarations of long double
functions in math.h. We don't normally test for these functions when
cross compiling, because link tests don't work, or ever really, but
not defining them as available causes replacements to be defined in
ways that may cause duplicate definition linker errors if the units
defining both the replacement and the actual implementation are
brought in because of other symbols.
for libstdc++-v3/ChangeLog
* crossconfig.m4 (GLIBCXX_CROSSCONFIG) [*-vxworks*]: Define
long double functions as available if declared by math.h.
(GLIBCXX_CHECK_MATH_DECL, GLIBCXX_CHECK_MATH_DECLS): New.
* configure: Rebuild.
From-SVN: r279731
Originally these functions were always inline. I changed them in r277342
to be always constexpr, then in r277588 changed them to be constexpr for
C++14, but I didn't restore the 'inline' for C++11. That leads to linker
errors when libstdc++.so is built unoptimized, because those functions
don't get instantiated in src/c++11/string-inst.o
PR libstdc++/92927
* include/bits/alloc_traits.h (__alloc_on_copy, __alloc_on_move)
(__alloc_on_swap): Add inline specifier.
From-SVN: r279656
* libsupc++/compare (common_comparison_category): Define without using
concepts and optimise for compilation time.
(__detail::__cmp_cat_ids): Remove.
(__detail::__common_cmp_cat): Replace class template and
specializations with constexpr function.
From-SVN: r279307
* include/pstl/glue_numeric_defs.h: Restore enable_if lost
during original import of pstl.
* include/pstl/glue_numeric_impl.h: Likewise.
From-SVN: r279212
As discussed at https://github.com/cplusplus/draft/issues/3534 two
std::span constructors specify incorrect conditions for throwing
exceptions. This patch makes those constructors have correct
noexcept-specifiers that accurately reflect what can actually throw.
(span(ContiguousIterator, Sentinel)): Add conditional noexcept.
* include/std/span (span(ContiguousIterator, size_type)): Change
noexcept to be unconditionally true.
* testsuite/23_containers/span/nothrow_cons.cc: New test.
From-SVN: r279206
The alias template wasn't working because it applied iter_reference_t to
the pack of iterators before and after passing the pack to the
__indeirect_result helper.
* include/bits/iterator_concepts.h (indirect_result_t): Do not apply
iter_reference_t to parameter pack.
* testsuite/24_iterators/indirect_callable/projected.cc: New test.
From-SVN: r279170
This change replaces the __forwarding_range implementation detail with
the ranges::safe_range concept and adds the ranges::enable_safe_range
variable template for opt-in in to the concept.
It also adjusts the begin/end/rbegin/rend customization point objects to
match the new rules for accessing rvalue ranges only when safe to do so.
* include/bits/range_access.h (ranges::enable_safe_range): Define.
(ranges::begin, ranges::end, ranges::rbegin, ranges::rend): Constrain
to only accept types satisfying safe_range and treat argument as an
lvalue when calling a member of performing ADL.
(ranges::__detail::__range_impl, ranges::__detail::__forwarding_range):
Remove.
(ranges::range): Adjust definition.
(ranges::safe_range): Define.
(ranges::iterator_t, ranges::range_difference_t): Reorder definitions
to match the synopsis in the working draft.
(ranges::disable_sized_range): Remove duplicate definition.
* include/experimental/string_view (ranges::enable_safe_range): Add
partial specialization for std::experimental::basic_string_view.
* include/std/ranges (ranges::viewable_range, ranges::subrange)
(ranges::empty_view, ranges::iota_view): Use safe_range. Specialize
enable_safe_range.
(ranges::safe_iterator_t, ranges::safe_subrange_t): Define.
* include/std/span (ranges::enable_safe_range): Add partial
specialization for std::span.
* include/std/string_view (ranges::enable_safe_range): Likewise for
std::basic_string_view.
* testsuite/std/ranges/access/begin.cc: Adjust expected results.
* testsuite/std/ranges/access/cbegin.cc: Likewise.
* testsuite/std/ranges/access/cdata.cc: Likewise.
* testsuite/std/ranges/access/cend.cc: Likewise.
* testsuite/std/ranges/access/crbegin.cc: Likewise.
* testsuite/std/ranges/access/crend.cc: Likewise.
* testsuite/std/ranges/access/data.cc: Likewise.
* testsuite/std/ranges/access/end.cc: Likewise.
* testsuite/std/ranges/access/rbegin.cc: Likewise.
* testsuite/std/ranges/access/rend.cc: Likewise.
* testsuite/std/ranges/empty_view.cc: Test ranges::begin and
ranges::end instead of unqualified calls to begin and end.
* testsuite/std/ranges/safe_range.cc: New test.
* testsuite/std/ranges/safe_range_types.cc: New test.
* testsuite/util/testsuite_iterators.h: Add comment about safe_range.
From-SVN: r279135
When concatenating a path ending in a root-directory onto another path,
we added an empty filename to the end of the path twice, but only
reserved space for one. That meant the second write went past the end of
the allocated buffer.
PR libstdc++/92853
* src/c++17/fs_path.cc (filesystem::path::operator+=(const path&)):
Do not process a trailing directory separator twice.
* testsuite/27_io/filesystem/path/concat/92853.cc: New test.
* testsuite/27_io/filesystem/path/concat/path.cc: Test more cases.
From-SVN: r279110
