1 // RUN: %clang_cc1 -fsyntax-only -Wmax-unsigned-zero -verify %s -std=c++11
2 // RUN: %clang_cc1 -fsyntax-only -Wmax-unsigned-zero %s -std=c++11 -fdiagnostics-parseable-fixits 2>&1 | FileCheck %s
3
4 namespace std {
5 template <typename T>
6 T max(const T &, const T &);
7 }
8
test(unsigned u)9 void test(unsigned u) {
10 auto a = std::max(55u, 0u);
11 // expected-warning@-1{{taking the max of a value and unsigned zero is always equal to the other value}}
12 // expected-note@-2{{remove call to max function and unsigned zero argument}}
13 // CHECK: fix-it:"{{.*}}":{[[@LINE-3]]:12-[[@LINE-3]]:20}:""
14 // CHECK: fix-it:"{{.*}}":{[[@LINE-4]]:24-[[@LINE-4]]:28}:""
15 auto b = std::max(u, 0u);
16 // expected-warning@-1{{taking the max of a value and unsigned zero is always equal to the other value}}
17 // expected-note@-2{{remove call to max function and unsigned zero argument}}
18 // fix-it:"/usr/local/google/home/rtrieu/clang/open/llvm/tools/clang/test/SemaCXX/warn-max-unsigned-zero.cpp":{13:12-13:20}:""
19 // fix-it:"/usr/local/google/home/rtrieu/clang/open/llvm/tools/clang/test/SemaCXX/warn-max-unsigned-zero.cpp":{13:22-13:26}:""
20 auto c = std::max(0u, 55u);
21 // expected-warning@-1{{taking the max of unsigned zero and a value is always equal to the other value}}
22 // expected-note@-2{{remove call to max function and unsigned zero argument}}
23 // fix-it:"/usr/local/google/home/rtrieu/clang/open/llvm/tools/clang/test/SemaCXX/warn-max-unsigned-zero.cpp":{16:12-16:20}:""
24 // fix-it:"/usr/local/google/home/rtrieu/clang/open/llvm/tools/clang/test/SemaCXX/warn-max-unsigned-zero.cpp":{16:21-16:24}:""
25 auto d = std::max(0u, u);
26 // expected-warning@-1{{taking the max of unsigned zero and a value is always equal to the other value}}
27 // expected-note@-2{{remove call to max function and unsigned zero argument}}
28 // fix-it:"/usr/local/google/home/rtrieu/clang/open/llvm/tools/clang/test/SemaCXX/warn-max-unsigned-zero.cpp":{19:12-19:20}:""
29 // fix-it:"/usr/local/google/home/rtrieu/clang/open/llvm/tools/clang/test/SemaCXX/warn-max-unsigned-zero.cpp":{19:21-19:24}:""
30 }
31
negative_test(signed s)32 void negative_test(signed s) {
33 auto a = std::max(0, s);
34 auto b = std::max(s, 0);
35 auto c = std::max(22, 0);
36 auto d = std::max(0, 22);
37 }
38
39 template <unsigned x>
template_test()40 unsigned template_test() {
41 return std::max(x, 0u);
42 // expected-warning@-1{{taking the max of a value and unsigned zero is always equal to the other value}}
43 // expected-note@-2{{remove call to max function and unsigned zero argument}}
44 // fix-it:"/usr/local/google/home/rtrieu/clang/open/llvm/tools/clang/test/SemaCXX/warn-max-unsigned-zero.cpp":{33:10-33:18}:""
45 // fix-it:"/usr/local/google/home/rtrieu/clang/open/llvm/tools/clang/test/SemaCXX/warn-max-unsigned-zero.cpp":{33:20-33:24}:""
46 }
47
48 int a = template_test<0>() + template_test<1>() + template_test<2>();
49
50 #define comp(x,y) std::max(x, y)
51
52 int b = comp(0, 1);
53 int c = comp(0u, 1u);
54 int d = comp(2u, 0u);
55
56