1 // RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -std=c++11 -Wuninitialized -verify %s
2
3 // test1: Expect no diagnostics
test1(int x)4 int test1(int x) {
5 int y;
6 asm goto("nop" : "=r"(y) : "r"(x) : : err);
7 return y;
8 err:
9 return -1;
10 }
11
test2(int x)12 int test2(int x) {
13 int y; // expected-warning {{variable 'y' is used uninitialized whenever its declaration is reached}} \
14 // expected-note {{initialize the variable}}
15 if (x < 42)
16 asm volatile goto("testl %0, %0; testl %1, %2; jne %l3" : "+S"(x), "+D"(y) : "r"(x) :: indirect_1, indirect_2);
17 else
18 asm volatile goto("testl %0, %1; testl %2, %3; jne %l5" : "+S"(x), "+D"(y) : "r"(x), "r"(y) :: indirect_1, indirect_2);
19 return x + y;
20 indirect_1:
21 return -42;
22 indirect_2:
23 return y; // expected-note {{uninitialized use occurs here}}
24 }
25
test3(int x)26 int test3(int x) {
27 int y; // expected-warning {{variable 'y' is used uninitialized whenever its declaration is reached}} \
28 // expected-note {{initialize the variable}}
29 asm goto("xorl %1, %0; jmp %l2" : "=&r"(y) : "r"(x) : : fail);
30 normal:
31 y += x;
32 return y;
33 if (x) {
34 fail:
35 return y; // expected-note {{uninitialized use occurs here}}
36 }
37 return 0;
38 }
39
test4(int x)40 int test4(int x) {
41 int y; // expected-warning {{variable 'y' is used uninitialized whenever its declaration is reached}} \
42 // expected-note {{initialize the variable}}
43 goto forward;
44 backward:
45 return y; // expected-note {{uninitialized use occurs here}}
46 forward:
47 asm goto("# %0 %1 %2" : "=r"(y) : "r"(x) : : backward);
48 return y;
49 }
50
51 // test5: Expect no diagnostics
test5(int x)52 int test5(int x) {
53 int y;
54 asm volatile goto("testl %0, %0; testl %1, %2; jne %l3" : "+S"(x), "+D"(y) : "r"(x) :: indirect, fallthrough);
55 fallthrough:
56 return y;
57 indirect:
58 return -2;
59 }
60