LLDB is currently always activating C++ when parsing expressions as LLDB itself
is using C++ features when creating the final AST that will be codegen'd
(specifically, references to variables, namespaces and using declarations are
used).
This is causing problems for users that have variables in non-C++ programs (e.g.
plain C or Objective-C) that have names which are keywords in C++. Expressions
referencing those variables fail to parse as LLDB's Clang parser thinks those
identifiers are C++ keywords and not identifiers that may belong to a
declaration.
We can't just disable C++ in the expression parser for those situations as
replacing the functionality of the injected C++ code isn't trivial. So this
patch is just disabling most keywords that are exclusive to C++ in LLDB's Clang
parser when we are in a non-C++ expression. There are a few keywords we can't
disable for now:
* `using` as that's currently used in some situations to inject variables into the expression function.
* `__null` as that's used by LLDB to define `NULL`/`Nil`/`nil`.
Getting rid of these last two keywords is possible but is a large enough change
that this will be handled in follow up patches.
Note that this only changes the keyword status of those tokens but this patch
does not remove any C++ functionality from the expression parser. The type
system still follows C++ rules and so does the rest of the expression parser.
There is another small change that gives the hardcoded macro definitions in LLDB
a higher precedence than the macros imported from the Objective-C modules. The
reason for this is that the Objective-C modules in LLDB are actually parsed in
Objective-C++ mode and they end up providing the C++ definitions of certain
system macros (like `NULL` being defined as `nullptr`). So we have to move the
LLDB definition forward and surround the definition from the module with an
`#ifdef` to make sure that we use the correct LLDB definition that doesn't
reference C++ keywords. Or to give an example, this is how the expression source
code changes:
Before:
```
#define NULL (nullptr) // injected module definition
#ifndef NULL
#define NULL (__null) // hardcoded LLDB definition
#endif
```
After:
```
#ifndef NULL
#define NULL (__null) // hardcoded LLDB definition
#endif
#ifndef NULL
#define NULL (nullptr) // injected module definition
#endif
```
Fixes rdar://10356912
Reviewed By: shafik
Differential Revision: https://reviews.llvm.org/D82770
Display null pointer as `nullptr`, `nil` and `NULL` for C++,
Objective-C/Objective-C++ and C respectively. The original motivation
for this patch was to display a null std::string pointer as nullptr
instead of "", but the fix seemed generic enough to be done for all
summary providers.
Differential revision: https://reviews.llvm.org/D77153
When parsing DWARF and laying out bit-fields we don't properly take into account when they are in a union, they will all have a zero offset.
Differential Revision: https://reviews.llvm.org/D91118
This adds `expect_var_path` to test variable paths so we no longer have to
use `frame var` and find substrs in the command output. The behaviour
is identical with `expect_expr` (and it also uses the same checking backend),
but it instead calls `GetValueForVariablePath` to evaluate the string as a variable
path.
Also rewrites a few of the tests that previously used `frame variable` to use
`expect_var_path`.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D90450
Make category-specifying files visible. There is really no good reason
to keep them hidden, and having them visible increases the chances
that someone will actually spot them.
Differential Revision: https://reviews.llvm.org/D91065
Replace the plethora of ObjC-implied 'skipUnlessDarwin' decorators
with marking tests as 'objc' category (whenever missing), and skip all
ObjC tests on non-Darwin platforms. I have used '.categories' file
wherever it was present already or all (>1) tests were relying on ObjC,
and explicit add_test_categories() where there was only one test.
Differential Revision: https://reviews.llvm.org/D91056
Use skipUnlessDarwin decorator for tests that are specific to Darwin,
instead of skipIf... for all other platforms. This should make it clear
that these tests are not supposed to work elsewhere. It will also make
these tests stop repeatedly popping up while I look for tests that could
be fixed on the platform in question.
Differential Revision: https://reviews.llvm.org/D91003
The new FreeBSDRemote plugin has reached feature parity on i386
and amd64 targets. Use it by default on these architectures, while
allowing the use of the legacy plugin via FREEBSD_LEGACY_PLUGIN envvar.
Revisit the method of switching plugins. Apparently, the return value
of PlatformFreeBSD::CanDebugProcess() is what really decides whether
the legacy or the new plugin is used.
Update the test status. Reenable the tests that were previously
disabled on FreeBSD and do not cause hangs or are irrelevant to FreeBSD.
Mark all tests that fail reliably as expectedFailure. For now, tests
that are flaky (i.e. produce unstable results) are left enabled
and cause unpredictable test failures.
Differential Revision: https://reviews.llvm.org/D90757
Displaying large packed bitfields did not work if one was accessing them
through a pointer, and he used the "->" notation ("[0]." notation is
fine). The reason for that is that implicit dereference in -> is plumbed
all the way down to ValueObjectChild::UpdateValue, where the process of
fetching the child value was forked for this flag. The bitfield
"sliding" code was implemented only for the branch which did not require
dereferencing.
This patch restructures the function to avoid this mistake. Processing
now happens in two stages.
- first the parent is dereferenced (if needed)
- then the child value is computed (this step includes sliding and is
common for both branches)
Differential Revision: https://reviews.llvm.org/D89236
This patch adds support for the _M and _m gdb-remote packets, which
(de)allocate memory in the inferior. This works by "injecting" a
m(un)map syscall into the inferior. This consists of:
- finding an executable page of memory
- writing the syscall opcode to it
- setting up registers according to the os syscall convention
- single stepping over the syscall
The advantage of this approach over calling the mmap function is that
this works even in case the mmap function is buggy or unavailable. The
disadvantage is it is more platform-dependent, which is why this patch
only works on X86 (_32 and _64) right now. Adding support for other
linux architectures should be easy and consist of defining the
appropriate syscall constants. Adding support for other OSes depends on
the its ability to do a similar trick.
Differential Revision: https://reviews.llvm.org/D89124
The problem here is in the "sliding" code in
ValueObjectChild::UpdateValue. It modifies m_bitfield_bit_offset and
m_value to ensure the bitfield value fits the window given by the
underlying type.
However, this is broken next time UpdateValue is called, because it
updates the m_value value from the parent. However, the value cannot be
slid again because the m_bitfield_bit_offset is already modified.
It seems this can happen only under specific circumstances. One way to
trigger is is to run an expression which can be interpreted (jitting it
causes a new StackFrame and ValueObject variables to be created).
I fix this bug by modifying m_byte_offset instead of m_scalar, and
ensuring the changes are folded into m_scalar regardless of how many
times UpdateValue is called.
Differential Revision: https://reviews.llvm.org/D88992
Add preconditions to `TestBase.expect()` that catch semantically invalid calls
that happen to succeed anyway. This also fixes the broken callsites caught by
these checks.
This prevents the following incorrect calls:
1. `self.expect("lldb command", "some substr")`
2. `self.expect("lldb command", "assert message", "some substr")`
Differential Revision: https://reviews.llvm.org/D88792
Clang has some type sugar that only serves as a way to preserve the way a user
has typed a certain type in the source code. These types are currently not
unwrapped when we query the type name for a Clang type, which means that this
type sugar actually influences what formatters are picked for a certain type.
Currently if a user decides to reference a type by doing `::GlobalDecl Var = 3;`,
the type formatter for `GlobalDecl` will not be used (as the type sugar
around the type gives it the name `::GlobalDecl`. The same goes for other ways
to spell out a type such as `auto` etc.
With this patch most of this type sugar gets stripped when the full type name is
calculated. Typedefs are not getting desugared as that seems counterproductive.
I also don't desugar atomic types as that's technically not type sugar.
Reviewed By: jarin
Differential Revision: https://reviews.llvm.org/D87481
The ASTImporter has an `Imported(From, To)` callback that notifies subclasses
that a declaration has been imported in some way. LLDB uses this in the
`CompleteTagDeclsScope` to see which records have been imported into the scratch
context. If the record was declared inside the expression, then the
`CompleteTagDeclsScope` will forcibly import the full definition of that record
to the scratch context so that the expression AST can safely be disposed later
(otherwise we might end up going back to the deleted AST to complete the
minimally imported record). The way this is implemented is that there is a list
of decls that need to be imported (`m_decls_to_complete`) and we keep completing
the declarations inside that list until the list is empty. Every `To` Decl we
get via the `Imported` callback will be added to the list of Decls to be
completed.
There are some situations where the ASTImporter will actually give us two
`Imported` calls with the same `To` Decl. One way where this happens is if the
ASTImporter decides to merge an imported definition into an already imported
one. Another way is that the ASTImporter just happens to get two calls to
`ASTImporter::Import` for the same Decl. This for example happens when importing
the DeclContext of a Decl requires importing the Decl itself, such as when
importing a RecordDecl that was declared inside a function.
The bug addressed in this patch is that when we end up getting two `Imported`
calls for the same `To` Decl, then we would crash in the
`CompleteTagDeclsScope`. That's because the first time we complete the Decl we
remove the Origin tracking information (that maps the Decl back to from where it
came from). The next time we try to complete the same `To` Decl the Origin
tracking information is gone and we hit the `to_context_md->getOrigin(decl).ctx
== m_src_ctx` assert (`getOrigin(decl).ctx` is a nullptr the second time as the
Origin was deleted).
This is actually a regression coming from D72495. Before D72495
`m_decls_to_complete` was actually a set so every declaration in there could
only be queued once to be completed. The set was changed to a vector to make the
iteration over it deterministic, but that also causes that we now potentially
end up trying to complete a Decl twice.
This patch essentially just reverts D72495 and makes the `CompleteTagDeclsScope`
use a SetVector for the list of declarations to be completed. The SetVector
should filter out the duplicates (as the original `set` did) and also ensure that
the completion order is deterministic. I actually couldn't find any way to cause
LLDB to reproduce this bug by merging declarations (this would require that we
for example declare two namespaces in a non-top-level expression which isn't
possible). But the bug reproduces very easily by just declaring a class in an
expression, so that's what the test is doing.
Reviewed By: shafik
Differential Revision: https://reviews.llvm.org/D85648
TestCPP11EnumTypes is one of the most expensive tests on my system and takes
around 35 seconds to run. A relatively large amount of that time is actually
doing CPU intensive work it seems (and not waiting on timeouts like other
slow tests).
The main issue is that this test repeatedly compiles the same source files
with different compiler defines. The test is also including standard library
headers, so it will also build all system modules with the gmodules debug
info variant. This leads to the problem that this test ends up compiling all
system Clang modules 8 times (one for each subtest with a unique define). As
the system modules are quite large, this causes that this test spends most
of its runtime just recompiling all system modules on macOS.
There is also the small issue that this test is starting and start-stopping
the test process a few hundred times.
This rewrites the test to instead just use a macro to instantiate all the
enum types in a single source and uses global variables to test the values
(which means there is no more need to continue/stop or even start a process).
I kept running all the debug info variants (event though it doesn't seem really
relevant) to keep this as NFC as possible.
This reduced the test runtime by around 1.5 seconds on my system (or in relative
numbers, the runtime of this test decreases by 95%).
TypeSystemClang::CreateTypedef was creating a typedef in the right
DeclContext, but it was not actually adding it as a child of the
context. The resulting inconsistent state meant that we would be unable
to reference the typedef from an expression directly, but we could use
them if they end up being pulled in by some previous subexpression
(because the ASTImporter will set up the correct links in the expression
ast).
This patch adds the typedef to the decl context it is created in.
Differential Revision: https://reviews.llvm.org/D86140
Rename the existing expectedFailure to expectedFailureIfFn to better
describe its purpose and provide an overload for
unittest2.expectedFailure in decorators.py.
Like the other type sugar removed by RemoveWrappingTypes, SubstTemplateTypeParm
is just pure sugar that should be ignored. If we don't ignore it (as we do now),
LLDB will fail to read values from record fields that have a
SubstTemplateTypeParm type.
Only way to produce such a type in LLDB is to either use the `import-std-module`
setting to get a template into the expression parser or just create your own
template directly in the expression parser which is what we do in the test.
Reviewed By: jarin
Differential Revision: https://reviews.llvm.org/D85132
Once we start the definition of an ObjCInterfaceDecl we won't attempt to ImportDeclContext
later on. Unlike RecordDecl case which uses DefinitionCompleter to force completeDefinition
we don't seem to have a similar mechanism for ObjCInterfaceDecl.
This fix was needed due to a bug we see in LLDB expression parsing where an initial expression
cause an ObjCInterfaceDecl to be defined and subsequent expressions during import do not call
ImportDeclContext and we can end up in a situation where ivars are imported out of order and not all ivars are imported.
Differential Revision: https://reviews.llvm.org/D83972
Currently expressions dealing with bit-fields in Objective-C objects is pretty broken. When generating debug-info for Objective-C bit-fields DW_AT_data_bit_offset has a different meaning than it does to C and C++.
When we parse the DWARF we validate bit offsets for C and C++ correctly but not for ObjC. For ObjC in some cases we end up incorrectly flagging an error and we don't generate further bit-fields in the AST.
Later on when we do a name lookup we don't find the ObjCIvarDecl in the ObjCInterfaceDecl in some cases since we never added it and then we don't go to the runtime to obtain the offset.
This will fix how we handle bit-fields for the Objective-C case and add tests to verify this fix but also to documents areas that still don't work and will be addressed in follow-up PRs.
Note: we can never correctly calculate offsets statically because of how Objective-C deals with the fragile base class issue. Which means the runtime may need to shift fields over.
Differential Revision: https://reviews.llvm.org/D83433
Template specializations are not handled in many of the
TypeSystemClang methods. For example, GetNumChildren does not handle
the TemplateSpecialization type class, so template specializations
always look like empty objects.
This patch just desugars template specializations in the existing
RemoveWrappingTypes desugaring helper.
Differential Revision: https://reviews.llvm.org/D83858
Summary:
Currently expect_expr will not run the expression if no target is selected. This
patch changes this behavior so that expect_expr will instead fall back to the
dummy target similar to what the `expression` command is doing. This way we
don't have to compile an empty executable to be able to use `expect_expr` (which
is a waste of resources for tests that just test generic type system features).
As a test I modernized the TestTypeOfDeclTypeExpr into a Python test +
expect_expr (as it relied on the dummy target fallback of the expression
command).
Reviewers: labath, JDevlieghere
Reviewed By: labath
Subscribers: abidh
Differential Revision: https://reviews.llvm.org/D83388
Currently the ItaniumRecordLayoutBuilder when laying out base classes has the virtual
and non-virtual bases mixed up when pulling the base class layouts from the external source.
This came up in an LLDB bug where on arm64 because of differences in how it deals with
tail padding would layout the bases differently without the correct layout from the
external source (LLDB). This would result in some fields being off by 4 bytes.
Differential Revision: https://reviews.llvm.org/D83008
and delete a bunch (but not all) redundant code. If you compare the remaining implementations of Platform*Simulator.cpp, there is still an obvious leftover cleanup task.
Specifically, this patch
- removes SDK initialization from dotest (there is equivalent but more
complete code in Makefile.rules)
- make Platform*Simulator inherit the generic implementation of
PlatformAppleSimulator (more can be done here)
- simplify the platform logic in Makefile.rules
- replace the custom SDK finding logic in Platform*Simulator with XcodeSDK
- adds a test for each supported simulator
Differential Revision: https://reviews.llvm.org/D81980
On the buildbot long and int have the same size but long and long long don't,
so the bug where we find the first type by size will produce a different error.
Make the test dynamic based on int/long/long long size to fix the bot.
Summary:
When we get an error back from IRForTarget we directly print that error to the
debugger output stream instead of putting it in the result object. The result
object only gets a vague "The expression could not be prepared to run in the
target" error message that doesn't actually tell the user what went wrong.
This patch just puts the IRForTarget errors into the status object that is
returned to the caller instead of directly printing it to the debugger. Also
updates one test that now can actually check for the error message it is
supposed to check for (instead of the default error which is all we had before).
Reviewers: JDevlieghere
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D81654
Before 539b47c9 this test was not actually using the debug_names section
because the -gdwarf added by Makefile.rules on windows overrode the
-gdwarf-5 flag from CFLAGS_EXTRAS. Now that -gdwarf-5 is respected, the
test is failing.
After this patch all remaining tests should pass on macOS when replayed
from a reproducer.
To capture the reproducers:
./bin/llvm-lit ../llvm-project/lldb/test/ --param lldb-run-with-repro=capture
To replay the reproducers:
./bin/llvm-lit ../llvm-project/lldb/test/ --param lldb-run-with-repro=replay
