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🍒 [cxx-interop] Prevent crash when importing a std::optional of nonescapable #84104

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Merged
merged 1 commit into from
Sep 4, 2025
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🍒 [cxx-interop] Prevent crash when importing a std::optional of nonescapable #84104

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15 changes: 13 additions & 2 deletions lib/ClangImporter/ImportDecl.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -2377,8 +2377,18 @@ namespace {
}

auto *vd = cast<VarDecl>(member);
if (!isNonEscapable) {
if (const auto *fd = dyn_cast<clang::FieldDecl>(nd))
auto getFieldDecl =
[](const clang::NamedDecl *decl) -> const clang::FieldDecl * {
if (const clang::FieldDecl *fd = dyn_cast<clang::FieldDecl>(decl))
return fd;
if (const clang::IndirectFieldDecl *ind =
dyn_cast<clang::IndirectFieldDecl>(decl))
return ind->getAnonField();
return nullptr;
};

if (!isNonEscapable && !decl->isAnonymousStructOrUnion()) {
if (const auto *fd = getFieldDecl(nd)) {
if (evaluateOrDefault(
Impl.SwiftContext.evaluator,
ClangTypeEscapability({fd->getType().getTypePtr(), &Impl}),
Expand All @@ -2391,6 +2401,7 @@ namespace {
decl->getLocation());
return nullptr;
}
}
}
members.push_back(vd);
}
Expand Down
89 changes: 68 additions & 21 deletions test/Interop/Cxx/class/nonescapable-errors.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -14,6 +14,7 @@ module Test {
//--- Inputs/nonescapable.h
#include "swift/bridging"
#include <vector>
#include <optional>

struct SWIFT_NONESCAPABLE View {
View() : member(nullptr) {}
Expand Down Expand Up @@ -99,54 +100,87 @@ struct SWIFT_ESCAPABLE Invalid {
View v;
};

struct SWIFT_NONESCAPABLE NonEscapable {};

template<typename T>
struct HasAnonUnion {
union {
int known;
T unknown;
};
};

template<typename T>
struct HasAnonStruct {
struct {
int known;
T unknown;
};
};

template<typename T>
struct SWIFT_NONESCAPABLE NonEscapableHasAnonUnion {
union {
int known;
T unknown;
};
};

using HasAnonUnionNonEscapable = HasAnonUnion<NonEscapable>;
using HasAnonStructNonEscapable = HasAnonStruct<NonEscapable>;
using NonEscapableHasAnonUnionNonEscapable = NonEscapableHasAnonUnion<NonEscapable>;
using NonEscapableOptional = std::optional<NonEscapable>;

//--- test.swift
import Test
import CxxStdlib

// CHECK: error: cannot find type 'Invalid' in scope
// CHECK: note: escapable record 'Invalid' cannot have non-escapable field 'v'
// CHECK-NO-LIFETIMES: error: cannot find type 'Invalid' in scope
// CHECK-NO-LIFETIMES: note: escapable record 'Invalid' cannot have non-escapable field 'v'
public func importInvalid(_ x: Invalid) {
}

// CHECK: error: a function with a ~Escapable result needs a parameter to depend on
// CHECK-NO-LIFETIMES: test.swift:11:32: error: a function cannot return a ~Escapable result
// CHECK-NO-LIFETIMES: test.swift:13:32: error: a function cannot return a ~Escapable result
public func noAnnotations() -> View {
// CHECK: nonescapable.h:16:7: warning: the returned type 'Owner' is annotated as escapable; it cannot have lifetime dependencies [#ClangDeclarationImport]
// CHECK-NO-LIFETIMES: nonescapable.h:16:7: warning: the returned type 'Owner' is annotated as escapable; it cannot have lifetime dependencies [#ClangDeclarationImport]
// CHECK: nonescapable.h:17:7: warning: the returned type 'Owner' is annotated as escapable; it cannot have lifetime dependencies [#ClangDeclarationImport]
// CHECK-NO-LIFETIMES: nonescapable.h:17:7: warning: the returned type 'Owner' is annotated as escapable; it cannot have lifetime dependencies [#ClangDeclarationImport]
f(nil)
// CHECK: nonescapable.h:20:7: warning: the returned type 'Owner' is annotated as escapable; it cannot have lifetime dependencies [#ClangDeclarationImport]
// CHECK-NO-LIFETIMES: nonescapable.h:20:7: warning: the returned type 'Owner' is annotated as escapable; it cannot have lifetime dependencies [#ClangDeclarationImport]
// CHECK: nonescapable.h:21:7: warning: the returned type 'Owner' is annotated as escapable; it cannot have lifetime dependencies [#ClangDeclarationImport]
// CHECK-NO-LIFETIMES: nonescapable.h:21:7: warning: the returned type 'Owner' is annotated as escapable; it cannot have lifetime dependencies [#ClangDeclarationImport]
// No duplicate warning for f2:
// CHECK-NOT: nonescapable.h:20
// CHECK-NOT: nonescapable.h:21
f2(nil, nil)
// CHECK: nonescapable.h:24:6: warning: the returned type 'View' is annotated as non-escapable; its lifetime dependencies must be annotated [#ClangDeclarationImport]
// CHECK-NO-LIFETIMES: nonescapable.h:24:6: warning: the returned type 'View' is annotated as non-escapable; its lifetime dependencies must be annotated [#ClangDeclarationImport]
// CHECK-NO-LIFETIMES: nonescapable.h:24:6: error: a function cannot return a ~Escapable result
// CHECK: nonescapable.h:25:6: warning: the returned type 'View' is annotated as non-escapable; its lifetime dependencies must be annotated [#ClangDeclarationImport]
// CHECK-NO-LIFETIMES: nonescapable.h:25:6: warning: the returned type 'View' is annotated as non-escapable; its lifetime dependencies must be annotated [#ClangDeclarationImport]
// CHECK-NO-LIFETIMES: nonescapable.h:25:6: error: a function cannot return a ~Escapable result
g(nil)
h1(nil)
// CHECK-NO-LIFETIMES: nonescapable.h:34:21: error: a function cannot return a ~Escapable result
h2(nil)
// CHECK-NO-LIFETIMES: nonescapable.h:35:21: error: a function cannot return a ~Escapable result
h2(nil)
// CHECK-NO-LIFETIMES: nonescapable.h:36:21: error: a function cannot return a ~Escapable result
h3(nil)
i1()
// CHECK: nonescapable.h:39:39: error: template parameter 'Missing' does not exist
// CHECK-NO-LIFETIMES: nonescapable.h:39:39: error: template parameter 'Missing' does not exist
// CHECK: nonescapable.h:40:39: error: template parameter 'Missing' does not exist
// CHECK-NO-LIFETIMES: nonescapable.h:40:39: error: template parameter 'Missing' does not exist
i2()
// CHECK: nonescapable.h:45:33: error: template parameter 'S' expected to be a type parameter
// CHECK-NO-LIFETIMES: nonescapable.h:45:33: error: template parameter 'S' expected to be a type parameter
// CHECK: nonescapable.h:46:33: error: template parameter 'S' expected to be a type parameter
// CHECK-NO-LIFETIMES: nonescapable.h:46:33: error: template parameter 'S' expected to be a type parameter
j1()
// CHECK-NO-LIFETIMES: nonescapable.h:63:41: error: a function cannot return a ~Escapable result
j2()
// CHECK-NO-LIFETIMES: nonescapable.h:64:41: error: a function cannot return a ~Escapable result
j2()
// CHECK-NO-LIFETIMES: nonescapable.h:65:41: error: a function cannot return a ~Escapable result
j3()
k1();
// CHECK-NO-LIFETIMES: nonescapable.h:70:15: error: a function cannot return a ~Escapable result
// CHECK-NO-LIFETIMES: nonescapable.h:71:15: error: a function cannot return a ~Escapable result
k2();
// CHECK-NO-LIFETIMES: nonescapable.h:71:22: error: a function cannot return a ~Escapable result
// CHECK-NO-LIFETIMES: nonescapable.h:72:22: error: a function cannot return a ~Escapable result
k3();
l1();
// CHECK: nonescapable.h:77:12: error: a function with a ~Escapable result needs a parameter to depend on
// CHECK-NO-LIFETIMES: nonescapable.h:77:12: error: a function cannot return a ~Escapable result
// CHECK: nonescapable.h:78:12: error: a function with a ~Escapable result needs a parameter to depend on
// CHECK-NO-LIFETIMES: nonescapable.h:78:12: error: a function cannot return a ~Escapable result
l2();
return View()
}
Expand All @@ -162,6 +196,19 @@ public func test3(_ x: inout View) {
// CHECK-NO-LIFETIMES: note: return type unavailable (cannot import)
// CHECK-NO-LIFETIMES: pointer to non-escapable type 'View' cannot be imported
}

public func anonymousUnions() {
_ = HasAnonUnionNonEscapable()
// CHECK: error: cannot find 'HasAnonUnionNonEscapable' in scope
// CHECK-NO-LIFETIMES: error: cannot find 'HasAnonUnionNonEscapable' in scope
_ = HasAnonStructNonEscapable()
// CHECK: error: cannot find 'HasAnonStructNonEscapable' in scope
// CHECK-NO-LIFETIMES: error: cannot find 'HasAnonStructNonEscapable' in scope
_ = NonEscapableHasAnonUnionNonEscapable()
_ = NonEscapableOptional()
// CHECK-NO-LIFETIMES: error: an initializer cannot return a ~Escapable result
}

// CHECK-NOT: error
// CHECK-NOT: warning
// CHECK-NO-LIFETIMES-NOT: error
Expand Down