[Lldb-commits] [lldb] [lldb] Infer MSInheritanceAttr for CXXRecordDecl with DWARF on Windows (PR #115177)

[Stefan Gränitz via lldb-commits]

================
@@ -2,23 +2,58 @@
 
 // Itanium ABI:
 // RUN: %clang --target=x86_64-pc-linux -gdwarf -c -o %t_linux.o %s
-// RUN: %lldb -f %t_linux.o -b -o "target variable mp" | FileCheck %s
+// RUN: %lldb -f %t_linux.o -b -o "target variable s1 s2 m1 m2 v1 v2 v3 v4" | FileCheck --check-prefix=CHECK-GNU %s
 //
-// CHECK: (char SI::*) mp = 0x0000000000000000
+// CHECK-GNU: (void (Single1::*)()) s1 = 0x00000000000000000000000000000000
+// CHECK-GNU: (void (Single2::*)()) s2 = 0x00000000000000000000000000000000
+// CHECK-GNU: (void (Multiple1::*)()) m1 = 0x00000000000000000000000000000000
+// CHECK-GNU: (void (Multiple2::*)()) m2 = 0x00000000000000000000000000000000
+// CHECK-GNU: (void (Virtual1::*)()) v1 = 0x00000000000000000000000000000000
+// CHECK-GNU: (void (Virtual2::*)()) v2 = 0x00000000000000000000000000000000
+// CHECK-GNU: (void (Virtual3::*)()) v3 = 0x00000000000000000000000000000000
+// CHECK-GNU: (void (Virtual4::*)()) v4 = 0x00000000000000000000000000000000
 
 // Microsoft ABI:
-// RUN: %clang_cl --target=x86_64-windows-msvc -c -gdwarf -o %t_win.obj -- %s
-// RUN: lld-link /out:%t_win.exe %t_win.obj /nodefaultlib /entry:main /debug
-// RUN: %lldb -f %t_win.exe -b -o "target variable mp" | FileCheck --check-prefix=CHECK-MSVC %s
+// RUN: %clang_cl --target=x86_64-windows-msvc -c -gdwarf -o %t_win.obj /GS- -- %s
+// RUN: lld-link /out:%t_win.exe %t_win.obj /entry:main /debug /nodefaultlib
+// RUN: %lldb -f %t_win.exe -b -o "target variable s1 s2 m1 m2 v1 v2 v3 v4" | FileCheck --check-prefix=CHECK-MSVC %s
 //
-// DWARF has no representation of MSInheritanceAttr, so we cannot determine the size
-// of member-pointers yet. For the moment, make sure we don't crash on such variables.
-// CHECK-MSVC: error: Unable to determine byte size.
+// CHECK-MSVC: (void (Single1::*)()) s1 = 0x0000000000000000
+// CHECK-MSVC: (void (Single2::*)()) s2 = 0x0000000000000000
+// CHECK-MSVC: (void (Multiple1::*)()) m1 = 0x00000000000000000000000000000000
+// CHECK-MSVC: (void (Multiple2::*)()) m2 = 0x00000000000000000000000000000000
+// CHECK-MSVC: (void (Virtual1::*)()) v1 = 0xffffffff000000000000000000000000
+// CHECK-MSVC: (void (Virtual2::*)()) v2 = 0xffffffff000000000000000000000000
+// CHECK-MSVC: (void (Virtual3::*)()) v3 = 0xffffffff000000000000000000000000
+// CHECK-MSVC: (void (Virtual4::*)()) v4 = 0xffffffff000000000000000000000000
 
-struct SI {
-  char si;
-};
+// clang-format off
+struct Single1 { void s1() {} };
+struct Single2 : Single1 { void s2() {} };
 
-char SI::*mp = &SI::si;
+struct Helper {};
+struct Multiple1 : Single1, Helper { void m1() {} };
+struct Multiple2 : Multiple1 { void m2() {} };
 
-int main() { return 0; }
+struct Virtual1 : virtual Single1 { void v1() {} };
+struct Virtual2 : Virtual1 { void v2() {} };
+struct Virtual3 : virtual Multiple1 { void v3() {} };
+struct Virtual4 : Virtual1, Helper { void v4() {} };
+
+void (Single1::*s1)() = nullptr;
+void (Single2::*s2)() = nullptr;
+void (Multiple1::*m1)() = nullptr;
+void (Multiple2::*m2)() = nullptr;
+void (Virtual1::*v1)() = nullptr;
+void (Virtual2::*v2)() = nullptr;
+void (Virtual3::*v3)() = nullptr;
+void (Virtual4::*v4)() = nullptr;
+
+int main(int argc, char *argv[]) {
+  Virtual1 vi1;
+  Virtual2 vi2;
+  Virtual3 vi3;
+  Virtual4 vi4;
+  int sum = sizeof(Single2) + sizeof(Multiple2);
----------------
weliveindetail wrote:

We need to force emission of type info to DWARF right now. That's reasonable, because Clang doesn't know that we need it to infer member-pointer sizes. I guess we could teach it to do so, but in most real-world scenarios this might be a non-issue.

https://github.com/llvm/llvm-project/pull/115177