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[LLDB] Add formatters for MSVC STL std::optional #149545

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Merged
merged 2 commits into from
Jul 21, 2025
Merged

[LLDB] Add formatters for MSVC STL std::optional #149545

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927e9c7
[LLDB] Add formatters for MSVC STL std::optional
Nerixyz Jul 18, 2025
9330d22
fix: move deref flags
Nerixyz Jul 18, 2025
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29 changes: 19 additions & 10 deletions lldb/source/Plugins/Language/CPlusPlus/CPlusPlusLanguage.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1545,20 +1545,10 @@ static void LoadLibStdcppFormatters(lldb::TypeCategoryImplSP cpp_category_sp) {
"std::bitset synthetic child", "^std::(__debug::)?bitset<.+>(( )?&)?$",
stl_deref_flags, true);

AddCXXSynthetic(
cpp_category_sp,
lldb_private::formatters::LibStdcppOptionalSyntheticFrontEndCreator,
"std::optional synthetic child", "^std::optional<.+>(( )?&)?$",
stl_deref_flags, true);

AddCXXSummary(cpp_category_sp,
lldb_private::formatters::StdlibCoroutineHandleSummaryProvider,
"libstdc++ std::coroutine_handle summary provider",
libstdcpp_std_coroutine_handle_regex, stl_summary_flags, true);
AddCXXSummary(cpp_category_sp,
lldb_private::formatters::GenericOptionalSummaryProvider,
"libstd++ std::optional summary provider",
"^std::optional<.+>(( )?&)?$", stl_summary_flags, true);
}

static lldb_private::SyntheticChildrenFrontEnd *
Expand Down Expand Up @@ -1648,6 +1638,17 @@ GenericForwardListSyntheticFrontEndCreator(CXXSyntheticChildren *children,
*valobj_sp);
}

static SyntheticChildrenFrontEnd *
GenericOptionalSyntheticFrontEndCreator(CXXSyntheticChildren *children,
lldb::ValueObjectSP valobj_sp) {
if (!valobj_sp)
return nullptr;

if (IsMsvcStlOptional(*valobj_sp))
return MsvcStlOptionalSyntheticFrontEndCreator(children, valobj_sp);
return LibStdcppOptionalSyntheticFrontEndCreator(children, valobj_sp);
}

/// Load formatters that are formatting types from more than one STL
static void LoadCommonStlFormatters(lldb::TypeCategoryImplSP cpp_category_sp) {
if (!cpp_category_sp)
Expand All @@ -1664,6 +1665,8 @@ static void LoadCommonStlFormatters(lldb::TypeCategoryImplSP cpp_category_sp) {
SyntheticChildren::Flags stl_synth_flags;
stl_synth_flags.SetCascades(true).SetSkipPointers(false).SetSkipReferences(
false);
SyntheticChildren::Flags stl_deref_flags = stl_synth_flags;
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Lets move this down where we actually use it

stl_deref_flags.SetFrontEndWantsDereference();

using StringElementType = StringPrinter::StringElementType;

Expand Down Expand Up @@ -1712,6 +1715,9 @@ static void LoadCommonStlFormatters(lldb::TypeCategoryImplSP cpp_category_sp) {
AddCXXSynthetic(cpp_category_sp, GenericForwardListSyntheticFrontEndCreator,
"std::forward_list synthetic children",
"^std::forward_list<.+>(( )?&)?$", stl_synth_flags, true);
AddCXXSynthetic(cpp_category_sp, GenericOptionalSyntheticFrontEndCreator,
"std::optional synthetic children",
"^std::optional<.+>(( )?&)?$", stl_deref_flags, true);

AddCXXSummary(cpp_category_sp, GenericSmartPointerSummaryProvider,
"MSVC STL/libstdc++ std::shared_ptr summary provider",
Expand Down Expand Up @@ -1739,6 +1745,9 @@ static void LoadCommonStlFormatters(lldb::TypeCategoryImplSP cpp_category_sp) {
TypeSummaryImplSP(new ScriptSummaryFormat(
stl_summary_flags,
"lldb.formatters.cpp.gnu_libstdcpp.ForwardListSummaryProvider")));
AddCXXSummary(cpp_category_sp, GenericOptionalSummaryProvider,
"MSVC STL/libstd++ std::optional summary provider",
"^std::optional<.+>(( )?&)?$", stl_summary_flags, true);
}

static void LoadMsvcStlFormatters(lldb::TypeCategoryImplSP cpp_category_sp) {
Expand Down
26 changes: 24 additions & 2 deletions lldb/source/Plugins/Language/CPlusPlus/GenericOptional.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,7 @@
#include "Generic.h"
#include "LibCxx.h"
#include "LibStdcpp.h"
#include "MsvcStl.h"
#include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
#include "lldb/DataFormatters/FormattersHelpers.h"
#include "lldb/Target/Target.h"
Expand All @@ -32,6 +33,7 @@ class GenericOptionalFrontend : public SyntheticChildrenFrontEnd {
enum class StdLib {
LibCxx,
LibStdcpp,
MsvcStl,
};

GenericOptionalFrontend(ValueObject &valobj, StdLib stdlib);
Expand Down Expand Up @@ -77,7 +79,8 @@ lldb::ChildCacheState GenericOptionalFrontend::Update() {
else if (m_stdlib == StdLib::LibStdcpp) {
if (ValueObjectSP payload = m_backend.GetChildMemberWithName("_M_payload"))
engaged_sp = payload->GetChildMemberWithName("_M_engaged");
}
} else if (m_stdlib == StdLib::MsvcStl)
engaged_sp = m_backend.GetChildMemberWithName("_Has_value");

if (!engaged_sp)
return lldb::ChildCacheState::eRefetch;
Expand Down Expand Up @@ -114,7 +117,12 @@ ValueObjectSP GenericOptionalFrontend::GetChildAtIndex(uint32_t _idx) {
ValueObjectSP candidate = val_sp->GetChildMemberWithName("_M_value");
if (candidate)
val_sp = candidate;
}
} else if (m_stdlib == StdLib::MsvcStl)
// Same issue as with LibCxx
val_sp = m_backend.GetChildMemberWithName("_Has_value")
->GetParent()
->GetChildAtIndex(0)
->GetChildMemberWithName("_Value");

if (!val_sp)
return ValueObjectSP();
Expand Down Expand Up @@ -143,3 +151,17 @@ SyntheticChildrenFrontEnd *formatters::LibcxxOptionalSyntheticFrontEndCreator(
GenericOptionalFrontend::StdLib::LibCxx);
return nullptr;
}

bool formatters::IsMsvcStlOptional(ValueObject &valobj) {
if (auto valobj_sp = valobj.GetNonSyntheticValue())
return valobj_sp->GetChildMemberWithName("_Has_value") != nullptr;
return false;
}

SyntheticChildrenFrontEnd *formatters::MsvcStlOptionalSyntheticFrontEndCreator(
CXXSyntheticChildren *, lldb::ValueObjectSP valobj_sp) {
if (valobj_sp)
return new GenericOptionalFrontend(
*valobj_sp, GenericOptionalFrontend::StdLib::MsvcStl);
return nullptr;
}
6 changes: 6 additions & 0 deletions lldb/source/Plugins/Language/CPlusPlus/MsvcStl.h
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Original file line number Diff line number Diff line change
Expand Up @@ -65,6 +65,12 @@ SyntheticChildrenFrontEnd *
MsvcStlListSyntheticFrontEndCreator(CXXSyntheticChildren *,
lldb::ValueObjectSP valobj_sp);

// MSVC STL std::optional<>
bool IsMsvcStlOptional(ValueObject &valobj);
SyntheticChildrenFrontEnd *
MsvcStlOptionalSyntheticFrontEndCreator(CXXSyntheticChildren *,
lldb::ValueObjectSP valobj_sp);

} // namespace formatters
} // namespace lldb_private

Expand Down
18 changes: 11 additions & 7 deletions ...es/data-formatter/data-formatter-stl/generic/optional/TestDataFormatterGenericOptional.py
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Original file line number Diff line number Diff line change
Expand Up @@ -3,12 +3,9 @@
from lldbsuite.test.lldbtest import *
from lldbsuite.test import lldbutil

USE_LIBSTDCPP = "USE_LIBSTDCPP"
USE_LIBCPP = "USE_LIBCPP"


class GenericOptionalDataFormatterTestCase(TestBase):
def do_test_with_run_command(self, stdlib_type):
def do_test_with_run_command(self):
"""Test that that file and class static variables display correctly."""

# This is the function to remove the custom formats in order to have a
Expand All @@ -21,7 +18,6 @@ def cleanup():

self.addTearDownHook(cleanup)

self.build(dictionary={stdlib_type: "1"})
self.runCmd("file " + self.getBuildArtifact("a.out"), CURRENT_EXECUTABLE_SET)

bkpt = self.target().FindBreakpointByID(
Expand Down Expand Up @@ -100,7 +96,8 @@ def cleanup():
## We are skipping gcc version less that 5.1 since this test requires -std=c++17
@skipIf(compiler="gcc", compiler_version=["<", "5.1"])
def test_with_run_command_libcpp(self):
self.do_test_with_run_command(USE_LIBCPP)
self.build(dictionary={"USE_LIBCPP": 1})
self.do_test_with_run_command()

@add_test_categories(["libstdcxx"])
## Clang 7.0 is the oldest Clang that can reliably parse newer libc++ versions
Expand All @@ -109,4 +106,11 @@ def test_with_run_command_libcpp(self):
## We are skipping gcc version less that 5.1 since this test requires -std=c++17
@skipIf(compiler="gcc", compiler_version=["<", "5.1"])
def test_with_run_command_libstdcpp(self):
self.do_test_with_run_command(USE_LIBSTDCPP)
self.build(dictionary={"USE_LIBSTDCPP": 1})
self.do_test_with_run_command()

@add_test_categories(["msvcstl"])
def test_with_run_command_msvcstl(self):
# No flags, because the "msvcstl" category checks that the MSVC STL is used by default.
self.build()
self.do_test_with_run_command()
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