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("" : "=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@-1 {{initialize the variable}}
15 if (x < 42)
16 asm goto("" : "+S"(x), "+D"(y) : "r"(x) :: indirect_1, indirect_2);
17 else
18 asm goto("" : "+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@-1 {{initialize the variable}}
29 asm goto("" : "=&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@-1 {{initialize the variable}}
43 goto forward;
44 backward:
45 return y; // expected-note {{uninitialized use occurs here}}
46 forward:
47 asm goto("" : "=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 goto("" : "+S"(x), "+D"(y) : "r"(x) :: indirect, fallthrough);
55 fallthrough:
56 return y;
57 indirect:
58 return -2;
59 }
60
61 // test6: Expect no diagnostics.
test6(unsigned int * x)62 int test6(unsigned int *x) {
63 unsigned int val;
64
65 // See through casts and unary operators.
66 asm goto("" : "=r" (*(unsigned int *)(&val)) ::: indirect);
67 *x = val;
68 return 0;
69 indirect:
70 return -1;
71 }
72
test7(int z)73 int test7(int z) {
74 int x; // expected-warning {{variable 'x' is used uninitialized whenever its declaration is reached}}
75 // expected-note@-1 {{initialize the variable 'x' to silence this warning}}
76 if (z)
77 asm goto ("":"=r"(x):::A1,A2);
78 return 0;
79 A1:
80 A2:
81 return x; // expected-note {{uninitialized use occurs here}}
82 }
83
test8()84 int test8() {
85 int x = 0; // expected-warning {{variable 'x' is used uninitialized whenever its declaration is reached}}
86 // expected-note@-1 {{variable 'x' is declared here}}
87 asm goto ("":"=r"(x):::A1,A2);
88 return 0;
89 A1:
90 A2:
91 return x; // expected-note {{uninitialized use occurs here}}
92 }
93