This is necessary to be able to build a libc++ module from preprocessed source
(due to the submodule std.new).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@302312 91177308-0d34-0410-b5e6-96231b3b80d8
To support this, an optional marker "#pragma clang module contents" is
recognized in module map files, and the rest of the module map file from that
point onwards is treated as the source of the module. Preprocessing a module
map produces the input module followed by the marker and then the preprocessed
contents of the module.
Ignoring line markers, a preprocessed module might look like this:
module A {
header "a.h"
}
#pragma clang module contents
#pragma clang module begin A
// ... a.h ...
#pragma clang module end
The preprocessed output generates line markers, which are not accepted by the
module map parser, so -x c++-module-map-cpp-output should be used to compile
such outputs.
A couple of major parts do not work yet:
1) The files that are listed in the module map must exist on disk, in order to
build the on-disk header -> module lookup table in the PCM file. To fix
this, we need the preprocessed output to track the file size and other stat
information we might use to build the lookup table.
2) Declaration ownership semantics don't work properly yet, since mapping from
a source location to a module relies on mapping from FileIDs to modules,
which we can't do if module transitions can occur in the middle of a file.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@302309 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds a fix-it for the -Wunguarded-availability warning. This fix-it
is similar to the Swift one: it suggests that you wrap the statement in an
`if (@available)` check. The produced fixits are indented (just like the Swift
ones) to make them look nice in Xcode's fix-it preview.
rdar://31680358
Differential Revision: https://reviews.llvm.org/D32424
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@302253 91177308-0d34-0410-b5e6-96231b3b80d8
The whitespace should come from the argument name in the macro
expansion, rather than from the token passed to the macro (same as it
does when not pasting).
Added a new test case for the change in behavior to stringize_space.c.
FileCheck'ized macro_paste_commaext.c, tweaked the test case, and
added a comment; no behavioral change to this test.
Differential Revision: https://reviews.llvm.org/D30427
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@302195 91177308-0d34-0410-b5e6-96231b3b80d8
These pragmas are intended to simulate the effect of entering or leaving a file
with an associated module. This is not completely implemented yet: declarations
between the pragmas will not be attributed to the correct module, but macro
visibility is already functional.
Modules named by #pragma clang module begin must already be known to clang (in
some module map that's either loaded or on the search path).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@302098 91177308-0d34-0410-b5e6-96231b3b80d8
Many of our supported configurations support modules but do not have any
first-class syntax to perform a module import. This leaves us with a problem:
there is no way to represent the expansion of a #include that imports a module
in the -E output for such languages. (We don't want to just leave it as a
#include because that requires the consumer of the preprocessed source to have
the same file system layout and include paths as the creator.)
This patch adds a new pragma:
#pragma clang module import MODULE.NAME.HERE
that imports a module, and changes -E and -frewrite-includes to use it when
rewriting a #include that maps to a module import. We don't make any attempt
to use a native language syntax import if one exists, to get more consistent
output. (If in the future, @import and #include have different semantics in
some way, the pragma will track the #include semantics.)
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@301725 91177308-0d34-0410-b5e6-96231b3b80d8
One of the -Wincomplete-umbrella warnings diagnoses when a header is present in
the directory but it's not present in the umbrella header. Currently, this
warning only happens on top level modules; any submodule using an umbrella
header does not get this warning. Fix that by also considering the submodules.
Differential Revision: https://reviews.llvm.org/D32576
rdar://problem/22623686
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@301597 91177308-0d34-0410-b5e6-96231b3b80d8
If a file search involves a header map, suppress
-Wnonportable-include-path. It's firing lots of false positives for
framework authors internally, and it's not trivial to fix.
Consider a framework called "Foo" with a main (installed) framework header
"Foo/Foo.h". It's atypical for "Foo.h" to actually live inside a
directory called "Foo" in the source repository. Instead, the
build system generates a header map while building the framework.
If Foo.h lives at the top-level of the source repository (common), and
the git repo is called ssh://some.url/foo.git, then the header map will
have something like:
Foo/Foo.h -> /Users/myname/code/foo/Foo.h
where "/Users/myname/code/foo" is the clone of ssh://some.url/foo.git.
After #import <Foo/Foo.h>, the current implementation of
-Wnonportable-include-path will falsely assume that Foo.h was found in a
nonportable way, because of the name of the git clone (.../foo/Foo.h).
However, that directory name was not involved in the header search at
all.
This commit adds an extra parameter to Preprocessor::LookupFile and
HeaderSearch::LookupFile to track if the search used a header map,
making it easy to suppress the warning. Longer term, once we find a way
to avoid the false positive, we should turn the warning back on.
rdar://problem/28863903
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@301592 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r301469. It isn't needed with r301470, which fixes
the API break introduced in the original commit.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@301472 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r301449. It breaks the build with:
MacroPPCallbacks.h:114:50: error: non-virtual member function marked 'override' hides virtual member function
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@301469 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The PPCallbacks::MacroUndefined callback is currently insufficient for clients that need to track the MacroDirectives.
This patch adds an additional argument to PPCallbacks::MacroUndefined that is the undef MacroDirective.
Reviewers: bruno, manmanren
Reviewed By: bruno
Subscribers: nemanjai, cfe-commits
Differential Revision: https://reviews.llvm.org/D29923
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@301449 91177308-0d34-0410-b5e6-96231b3b80d8
Drive-by fix (noticed while working on https://reviews.llvm.org/D32205):
DebugOverflowStack() is supposed to provoke a stack overflow, however
LLVM was smart enough to use the red-zone and fold the load into a tail
jump on x86_64 optimizing this to an endless loop instead of a stack
overflow.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@301218 91177308-0d34-0410-b5e6-96231b3b80d8
This commit teaches Clang to recognize editor placeholders that are produced
when an IDE like Xcode inserts a code-completion result that includes a
placeholder. Now when the lexer sees a placeholder token, it emits an
'editor placeholder in source file' error and creates an identifier token
that represents the placeholder. The parser/sema can now recognize the
placeholders and can suppress the diagnostics related to the placeholders. This
ensures that live issues in an IDE like Xcode won't get spurious diagnostics
related to placeholders.
This commit also adds a new compiler option named '-fallow-editor-placeholders'
that silences the 'editor placeholder in source file' error. This is useful
for an IDE like Xcode as we don't want to display those errors in live issues.
rdar://31581400
Differential Revision: https://reviews.llvm.org/D32081
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@300667 91177308-0d34-0410-b5e6-96231b3b80d8
Previously, if an escaped newline was followed by a newline or a nul, we'd lex
the escaped newline as a bogus space character. This led to a bunch of
different broken corner cases:
For the pattern "\\\n\0#", we would then have a (horizontal) space whose
spelling ends in a newline, and would decide that the '#' is at the start of a
line, and incorrectly start preprocessing a directive in the middle of a
logical source line. If we were already in the middle of a directive, this
would result in our attempting to process multiple directives at the same time!
This resulted in crashes, asserts, and hangs on invalid input, as discovered by
fuzz-testing.
For the pattern "\\\n" at EOF (with an implicit following nul byte), we would
produce a bogus trailing space character with spelling "\\\n". This was mostly
harmless, but would lead to clang-format getting confused and misformatting in
rare cases. We now produce a trailing EOF token with spelling "\\\n",
consistent with our handling for other similar cases -- an escaped newline is
always part of the token containing the next character, if any.
For the pattern "\\\n\n", this was somewhat more benign, but would produce an
extraneous whitespace token to clients who care about preserving whitespace.
However, it turns out that our lexing for line comments was relying on this bug
due to an off-by-one error in its computation of the end of the comment, on the
slow path where the comment might contain escaped newlines.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@300515 91177308-0d34-0410-b5e6-96231b3b80d8
This allows using and testing these two features separately. (noteably,
debug info is, so far as I know, always a win (basically). But function
modular codegen is currently a loss for highly optimized code - where
most of the linkonce_odr definitions are optimized away, so providing
weak_odr definitions is only overhead)
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@300104 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: When using the C preprocessor with assembly files, either with a
capital `S` file extension, or with `-xassembler-with-cpp`, the Unicode escape
sequence `\u` is ignored. The `\u` pattern can be used for expanding a macro
argument that starts with `u`.
Author: Salman Arif <salman.arif@arm.com>
Reviewers: rengolin, olista01
Reviewed By: olista01
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D31765
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@299754 91177308-0d34-0410-b5e6-96231b3b80d8
Fix the current parsing of subframeworks in modulemaps to lookup for
headers based on whether they are frameworks.
rdar://problem/30563982
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@298391 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r298185, effectively reapplying r298165, after fixing the
new unit tests (PR32338). The memory buffer generator doesn't null-terminate
the MemoryBuffer it creates; this version of the commit informs getMemBuffer
about that to avoid the assert.
Original commit message follows:
----
Clang's internal build system for implicit modules uses lock files to
ensure that after a process writes a PCM it will read the same one back
in (without contention from other -cc1 commands). Since PCMs are read
from disk repeatedly while invalidating, building, and importing, the
lock is not released quickly. Furthermore, the LockFileManager is not
robust in every environment. Other -cc1 commands can stall until
timeout (after about eight minutes).
This commit changes the lock file from being necessary for correctness
to a (possibly dubious) performance hack. The remaining benefit is to
reduce duplicate work in competing -cc1 commands which depend on the
same module. Follow-up commits will change the internal build system to
continue after a timeout, and reduce the timeout. Perhaps we should
reconsider blocking at all.
This also fixes a use-after-free, when one part of a compilation
validates a PCM and starts using it, and another tries to swap out the
PCM for something new.
The PCMCache is a new type called MemoryBufferCache, which saves memory
buffers based on their filename. Its ownership is shared by the
CompilerInstance and ModuleManager.
- The ModuleManager stores PCMs there that it loads from disk, never
touching the disk if the cache is hot.
- When modules fail to validate, they're removed from the cache.
- When a CompilerInstance is spawned to build a new module, each
already-loaded PCM is assumed to be valid, and is frozen to avoid
the use-after-free.
- Any newly-built module is written directly to the cache to avoid the
round-trip to the filesystem, making lock files unnecessary for
correctness.
Original patch by Manman Ren; most testcases by Adrian Prantl!
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@298278 91177308-0d34-0410-b5e6-96231b3b80d8
Clang's internal build system for implicit modules uses lock files to
ensure that after a process writes a PCM it will read the same one back
in (without contention from other -cc1 commands). Since PCMs are read
from disk repeatedly while invalidating, building, and importing, the
lock is not released quickly. Furthermore, the LockFileManager is not
robust in every environment. Other -cc1 commands can stall until
timeout (after about eight minutes).
This commit changes the lock file from being necessary for correctness
to a (possibly dubious) performance hack. The remaining benefit is to
reduce duplicate work in competing -cc1 commands which depend on the
same module. Follow-up commits will change the internal build system to
continue after a timeout, and reduce the timeout. Perhaps we should
reconsider blocking at all.
This also fixes a use-after-free, when one part of a compilation
validates a PCM and starts using it, and another tries to swap out the
PCM for something new.
The PCMCache is a new type called MemoryBufferCache, which saves memory
buffers based on their filename. Its ownership is shared by the
CompilerInstance and ModuleManager.
- The ModuleManager stores PCMs there that it loads from disk, never
touching the disk if the cache is hot.
- When modules fail to validate, they're removed from the cache.
- When a CompilerInstance is spawned to build a new module, each
already-loaded PCM is assumed to be valid, and is frozen to avoid
the use-after-free.
- Any newly-built module is written directly to the cache to avoid the
round-trip to the filesystem, making lock files unnecessary for
correctness.
Original patch by Manman Ren; most testcases by Adrian Prantl!
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@298165 91177308-0d34-0410-b5e6-96231b3b80d8
in macro argument pre-expansion mode when skipping a function body
This commit fixes a token caching problem that currently occurs when clang is
skipping a function body (e.g. when looking for a code completion token) and at
the same time caching the tokens for _Pragma when lexing it in macro argument
pre-expansion mode.
When _Pragma is being lexed in macro argument pre-expansion mode, it caches the
tokens so that it can avoid interpreting the pragma immediately (as the macro
argument may not be used in the macro body), and then either backtracks over or
commits these tokens. The problem is that, when we're backtracking/committing in
such a scenario, there's already a previous backtracking position stored in
BacktrackPositions (as we're skipping the function body), and this leads to a
situation where the cached tokens from the pragma (like '(' 'string_literal'
and ')') will remain in the cached tokens array incorrectly even after they're
consumed (in the case of backtracking) or just ignored (in the case when they're
committed). Furthermore, what makes it even worse, is that because of a previous
backtracking position, the logic that deals with when should we call
ExitCachingLexMode in CachingLex no longer works for us in this situation, and
more tokens in the macro argument get cached, to the point where the EOF token
that corresponds to the macro argument EOF is cached. This problem leads to all
sorts of issues in code completion mode, where incorrect errors get presented
and code completion completely fails to produce completion results.
rdar://28523863
Differential Revision: https://reviews.llvm.org/D28772
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@296140 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: This is a patch for PR31836. As the bug replaces the path separators in the included file name with the characters following them, the test script makes sure that there's no "Ccase-insensitive-include-pr31836.h" in the warning message.
Reviewers: rsmith, eric_niebler
Reviewed By: eric_niebler
Subscribers: karies, cfe-commits
Differential Revision: https://reviews.llvm.org/D30000
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@295779 91177308-0d34-0410-b5e6-96231b3b80d8
The Module::WithCodegen flag was only being set when the module was
parsed from a ModuleMap. Instead set it late, in the ASTWriter to match
the layer where the MODULAR_CODEGEN_DECLs list is determined (the
WithCodegen flag essentially means "are this module's decls in
MODULAR_CODEGEN_DECLs").
When simultaneous emission of AST file and modular object is implemented
this may need to change - the Module::WithCodegen flag will need to be
set earlier, and ideally the MODULAR_CODEGEN_DECLs gathering will
consult this flag (that's not possible right now since Decls destined
for an AST File don't have a Module - only if they're /read/ from a
Module is that true - I expect that would need to change as well).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@293692 91177308-0d34-0410-b5e6-96231b3b80d8
First pass at generating weak definitions of inline functions from module files
(& skipping (-O0) or emitting available_externally (optimizations)
definitions where those modules are used).
External functions defined in modules are emitted into the modular
object file as well (this may turn an existing ODR violation (if that
module were imported into multiple translations) into valid/linkable
code).
Internal symbols (static functions, for example) are not correctly
supported yet. The symbol will be produced, internal, in the modular
object - unreferenceable from the users.
Reviewers: rsmith
Differential Revision: https://reviews.llvm.org/D28845
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@293456 91177308-0d34-0410-b5e6-96231b3b80d8
by providing a memchr builtin that returns char* instead of void*.
Also add a __has_feature flag to indicate the presence of constexpr forms of
the relevant <string> functions.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@292555 91177308-0d34-0410-b5e6-96231b3b80d8
When a textual header is present inside a umbrella dir but not in the
header, we get the misleading warning:
warning: umbrella header for module 'FooFramework' does not include
header 'Baz_Private.h'
The module map in question:
framework module FooFramework {
umbrella header "FooUmbrella.h"
export *
module * { export * }
module Private {
textual header "Baz_Private.h"
}
}
Fix this by taking textual headers into account.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@291794 91177308-0d34-0410-b5e6-96231b3b80d8
In r276159, we started to say that a module X is defined in a pch if we specify
-fmodule-name when building the pch. This caused a regression that reports
module X is defined in both pch and pcm if we generate the pch with
-fmodule-name=X and then in a separate clang invocation, we include the pch and
also import X.pcm.
This patch adds an option CompilingPCH similar to CompilingModule. When we use
-fmodule-name=X while building a pch, modular headers in X will be textually
included and the compiler knows that we are not building module X, so we don't
put module X in SUBMODULE_DEFINITION of the pch.
Differential Revision: http://reviews.llvm.org/D28415
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@291465 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The module system supports accompanying a primary module (say Foo) with
an auxiliary "private" module (defined in an adjacent module.private.modulemap
file) that augments the primary module when associated private headers are
available. The feature is intended to be used to augment the primary
module with a submodule (say Foo.Private), however some users in the wild
are choosing to augment the primary module with an additional top-level module
with a "similar" name (in all cases so far: FooPrivate).
This "works" when a user of the module initially imports a private header,
such as '#import "Foo/something_private.h"' since the Foo import winds up
importing FooPrivate in passing. But if the import is subsequently recorded
in a PCH file, reloading the PCH will fail to validate because of a cross-check
that attempts to find the module.modulemap (or module.private.modulemap) using
HeaderSearch algorithm, applied to the "FooPrivate" name. Since it's stored in
Foo.framework/Modules, not FooPrivate.framework/Modules, the check fails and
the PCH is rejected.
This patch adds a compensatory workaround in the HeaderSearch algorithm
when searching (and failing to find) a module of the form FooPrivate: the
name used to derive filesystem paths is decoupled from the module name
being searched for, and if the initial search fails and the module is
named "FooPrivate", the filesystem search name is altered to remove the
"Private" suffix, and the algorithm is run a second time (still looking for
a module named FooPrivate, but looking in directories derived from Foo).
Accompanying this change is a new warning that triggers when a user loads
a module.private.modulemap that defines a top-level module with a different
name from the top-level module defined in its adjacent module.modulemap.
Reviewers: doug.gregor, manmanren, bruno
Subscribers: bruno, cfe-commits
Differential Revision: https://reviews.llvm.org/D27852
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@290219 91177308-0d34-0410-b5e6-96231b3b80d8
Include headermaps (.hmap files) in the .cache directory and
add VFS entries. All headermaps are known after HeaderSearch
setup, collect them right after.
rdar://problem/27913709
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@289360 91177308-0d34-0410-b5e6-96231b3b80d8
PCH files store the macro history for a given macro, and the whole history list
for one identifier is given to the Preprocessor at once via
Preprocessor::setLoadedMacroDirective(). This contained an assert that no macro
history exists yet for that identifier. That's usually true, but it's not true
for builtin macros, which are created in Preprocessor() before flags and pchs
are processed. Luckily, ASTWriter stops writing macro history lists at builtins
(see shouldIgnoreMacro() in ASTWriter.cpp), so the head of the history list was
missing for builtin macros. So make the assert weaker, and splice the history
list to the existing single define for builtins.
https://reviews.llvm.org/D27545
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@289228 91177308-0d34-0410-b5e6-96231b3b80d8
Recover better from an incompatible .pcm file being provided by -fmodule-file=. We try to include the headers of the module textually in this case, still enforcing the modules semantic rules. In order to make that work, we need to still track that we're entering and leaving the module. Also, if the module was also marked as unavailable (perhaps because it was missing a file), we shouldn't mark the module unavailable -- we don't need the module to be complete if we're going to enter it textually.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@288741 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r288449.
I believe that this is currently faulty wrt. modules being imported
inside namespaces. Adding these lines to the new test:
namespace n {
#include "foo.h"
}
Makes it break with
fatal error: import of module 'M' appears within namespace 'n'
However, I believe it should fail with
error: redundant #include of module 'M' appears within namespace 'n'
I have tracked this down to us now inserting a tok::annot_module_begin
instead of a tok::annot_module_include in
Preprocessor::HandleIncludeDirective() and then later in
Parser::parseMisplacedModuleImport(), we hit the code path for
tok::annot_module_begin, which doesn't set FromInclude of
checkModuleImportContext to true (thus leading to the "wrong"
diagnostic).
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@288626 91177308-0d34-0410-b5e6-96231b3b80d8
We try to include the headers of the module textually in this case, still
enforcing the modules semantic rules. In order to make that work, we need to
still track that we're entering and leaving the module. Also, if the module was
also marked as unavailable (perhaps because it was missing a file), we
shouldn't mark the module unavailable -- we don't need the module to be
complete if we're going to enter it textually.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@288449 91177308-0d34-0410-b5e6-96231b3b80d8
Thi way the compiler can pick the optimal storage duration. It's also
more readable. No functional change intended.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@287005 91177308-0d34-0410-b5e6-96231b3b80d8
Since array parameters decay to pointers, '_Nullable' and friends
should be available for use there as well. This is especially
important for parameters that are typedefs of arrays. The unsugared
syntax for this follows the syntax for 'static'-sized arrays in C:
void test(int values[_Nullable]);
This syntax was previously accepted but the '_Nullable' (and any other
attributes) were silently discarded. However, applying '_Nullable' to
a typedef was previously rejected and is now accepted; therefore, it
may be necessary to test for the presence of this feature:
#if __has_feature(nullability_on_arrays)
One important change here is that DecayedTypes don't always
immediately contain PointerTypes anymore; they may contain an
AttributedType instead. This only affected one place in-tree, so I
would guess it's not likely to cause problems elsewhere.
This commit does not change -Wnullability-completeness just yet. I
want to think about whether it's worth doing something special to
avoid breaking existing clients that compile with -Werror. It also
doesn't change '#pragma clang assume_nonnull' behavior, which
currently treats the following two declarations as equivalent:
#pragma clang assume_nonnull begin
void test(void *pointers[]);
#pragma clang assume_nonnull end
void test(void * _Nonnull pointers[]);
This is not the desired behavior, but changing it would break
backwards-compatibility. Most likely the best answer is going to be
adding a new warning.
Part of rdar://problem/25846421
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@286519 91177308-0d34-0410-b5e6-96231b3b80d8
which guarantee pointers are not null. These all seem to have useful
properties and correlations to document, in one case we even had it in
a comment but now it will also be an assert.
This should prevent PVS-Studio from incorrectly claiming that there are
a bunch of potential bugs here. But I feel really strongly that the
PVS-Studio warnings that pointed at this code have a far too high
false-positive rate to be entirely useful. These are just places where
there did seem to be a useful invariant to document and verify with an
assert. Several other places in the code were already correct and
already have perfectly clear code documenting and validating their
invariants, but still ran afoul of PVS-Studio.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@285985 91177308-0d34-0410-b5e6-96231b3b80d8
Richard Smith