clang AST crashes on invalid decl type.Assertion `getType(Base)->isPointerType() || getType(Base)->isArrayType()' failed

[mainsea]

The provided test case contains compilation errors, and in clang/lib/AST/APValue.cpp, the method QualType APValue::LValueBase::getType() const is noted to handle ValueDecl in an inadequate way for similar situations.

// FIXME: It's unclear where we're supposed to take the type from, and
// this actually matters for arrays of unknown bound. Eg:
//
// extern int arr[]; void f() { extern int arr[3]; };
// constexpr int *p = &arr[1]; // valid?
//
// For now, we take the most complete type we can find.

The possible reason is that the obtained decl is an invalid decl, causing it to lose its int[] type attribute.

crash example like:

extern int error_names_array[total_error_count + 2];
extern int error_names_array[];
static int *sqlstate_map = &error_names_array[1];

Is this a common way of handling the situation? When Clang detects a compilation error, certain unhandled cases can cause the Clang frontend to crash.However, in my opinion, it should at least not result in a crash.

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: mainsea (mainsea)

The provided test case contains compilation errors, and in clang/lib/AST/APValue.cpp, the method QualType APValue::LValueBase::getType() const is noted to handle ValueDecl in an inadequate way for similar situations.
>// FIXME: It's unclear where we're supposed to take the type from, and
// this actually matters for arrays of unknown bound. Eg:
//
// extern int arr[]; void f() { extern int arr[3]; };
// constexpr int *p = &arr[1]; // valid?
//
// For now, we take the most complete type we can find.

The possible reason is that the obtained decl is an invalid decl, causing it to lose its int[] type attribute.

crash example like:

extern int error_names_array[total_error_count + 2];
extern int error_names_array[];
static int *sqlstate_map = &error_names_array[1];

Is this a common way of handling the situation? When Clang detects a compilation error, certain unhandled cases can cause the Clang frontend to crash.However, in my opinion, it should at least not result in a crash.

[shafik]

ICE is always a bug but we have a duplicate here: #69468