struct Struct
{
int x = 3;
int foo()
{
int y = 5;
int nested()
{
int z = 7;
return x + y + z;
}
return nested();
}
}
int main()
{
return Struct().foo();
}
When compiled with -g, this shows a variable in nested() called "this", but is not the struct, but the capture of the outer function:
(00004C) S_GPROC32: [0000:00000000], Cb: 0000002B, Type: 0x1004, dg.Struct.foo.nested
Parent: 00000000, End: 00000000, Next: 00000000
Debug start: 0000000C, Debug end: 00000026
(000088) S_REGREL32: rbp+00000010, Type: 0x1019, this
(0000A0) S_ENDARG
(0000A4) S_REGREL32: rbp+FFFFFFF8, Type: T_INT4(0074), z
(0000B4) S_END
The type of "this" used to be void*, but has recently been populated with the captured stack variables of the outer function:
0x1016 : Length = 42, Leaf = 0x1505 LF_STRUCTURE
# members = 2, field list type 0x1017,
Derivation list type 0x0000, VT shape type 0x0000
Size = 0, class name = CAPTURE.dg.Struct.foo
0x1017 : Length = 34, Leaf = 0x1203 LF_FIELDLIST
list[0] = LF_MEMBER, public, type = 0x1015, offset = 16
member name = 'this'
list[1] = LF_MEMBER, public, type = 0x1002, offset = (LF_SHORT) -8
member name = 'y'
0x1019 : Length = 10, Leaf = 0x1002 LF_POINTER
Pointer (__ptr64), Size: 8
Element type : 0x1016
Note the "this" member of the capture struct. Having multiple "this" variables confuses both the debugger and the user.