[lldb-dev] lldb 11.0.0-rc2 different behavior then gdb.

[Chirag Patel via lldb-dev]

Hello all,

While debugging and printing struct with multi-dimensional char array, gdb successfully prints string while lldb bails out with only printing address.
For simple C testcase,

struct b {
        char i[2][4];
};

int main() {
        struct b z;
        z.i[0][0] = 'F';
        z.i[0][1] = 'O';
        z.i[0][2] = 'O';
        z.i[0][3] = 0;
        z.i[1][0] = 'B';
        z.i[1][1] = 'A';
        z.i[1][2] = 'R';
        z.i[1][3] = 0;
        return 0;
}

On gdb,
Reading symbols from /home/chirag/a.out...done.
(gdb) l
1       struct b {
2               char i[2][4];
3       };
4
5       int main() {
6               struct b z;
7               z.i[0][0] = 'F';
8               z.i[0][1] = 'O';
9               z.i[0][2] = 'O';
10              z.i[0][3] = 0;
(gdb) l
11              z.i[1][0] = 'B';
12              z.i[1][1] = 'A';
13              z.i[1][2] = 'R';
14              z.i[1][3] = 0;
15              return 0;
16      }
(gdb) b 15
Breakpoint 1 at 0x400511: file Desktop/test/struct.c, line 15.
(gdb) r
Starting program: /home/chirag/./a.out

Breakpoint 1, main () at Desktop/test/struct.c:15
15              return 0;
Missing separate debuginfos, use: debuginfo-install glibc-2.17-307.el7.1.x86_64
(gdb) p z
$1 = {i = {"FOO", "BAR"}}
(gdb) q
A debugging session is active.

While on lldb 11.0.0-rc2, (lldb) target create "/home/chirag/a.out"
Current executable set to '/home/chirag/a.out' (x86_64).
(lldb) b 15
Breakpoint 1: where = a.out`main + 36 at struct.c:15, address = 0x0000000000400511
(lldb) r
Process 57100 launched: '/home/chirag/a.out' (x86_64)
Process 57100 stopped
* thread #1, name = 'a.out', stop reason = breakpoint 1.1
    frame #0: 0x0000000000400511 a.out`main at struct.c:15
   12           z.i[1][1] = 'A';
   13           z.i[1][2] = 'R';
   14           z.i[1][3] = 0;
-> 15           return 0;
   16   }
(lldb) p z
(b) $0 = (i = char [2][4] @ 0x0000000001fe3ca0)
(lldb) q

It seems like the type summary formatter is failing? Or is it the intended behaviour?.

Thanks and Regards,
Chirag Patel.
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