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// RUN: %clang_analyze_cc1 \
// RUN: -analyzer-checker=core,apiModeling.llvm.ReturnValue \
// RUN: -analyzer-output=text -verify %s
struct Foo { int Field; };
bool problem();
void doSomething();
// Test the normal case when the implementation of MCAsmParser::Error() (one of
// the methods modeled by this checker) is opaque.
namespace test_normal {
struct MCAsmParser {
static bool Error();
};
bool parseFoo(Foo &F) {
if (problem()) {
// expected-note@-1 {{Assuming the condition is false}}
// expected-note@-2 {{Taking false branch}}
return MCAsmParser::Error();
}
F.Field = 0;
// expected-note@-1 {{The value 0 is assigned to 'F.Field'}}
return false;
}
bool parseFile() {
Foo F;
if (parseFoo(F)) {
// expected-note@-1 {{Calling 'parseFoo'}}
// expected-note@-2 {{Returning from 'parseFoo'}}
// expected-note@-3 {{Taking false branch}}
return true;
}
// The following expression would produce the false positive report
// "The left operand of '==' is a garbage value"
// without the modeling done by apiModeling.llvm.ReturnValue:
if (F.Field == 0) {
// expected-note@-1 {{Field 'Field' is equal to 0}}
// expected-note@-2 {{Taking true branch}}
doSomething();
}
// Trigger a zero division to get path notes:
(void)(1 / F.Field);
// expected-warning@-1 {{Division by zero}}
// expected-note@-2 {{Division by zero}}
return false;
}
} // namespace test_normal
// Sanity check for the highly unlikely case where the implementation of the
// method breaks the convention.
namespace test_break {
struct MCAsmParser {
static bool Error() {
return false;
}
};
bool parseFoo(Foo &F) {
if (problem()) {
// expected-note@-1 {{Assuming the condition is false}}
// expected-note@-2 {{Taking false branch}}
return !MCAsmParser::Error();
}
F.Field = 0;
// expected-note@-1 {{The value 0 is assigned to 'F.Field'}}
return MCAsmParser::Error();
// expected-note@-1 {{'MCAsmParser::Error' returned false, breaking the convention that it always returns true}}
}
bool parseFile() {
Foo F;
if (parseFoo(F)) {
// expected-note@-1 {{Calling 'parseFoo'}}
// expected-note@-2 {{Returning from 'parseFoo'}}
// expected-note@-3 {{Taking false branch}}
return true;
}
(void)(1 / F.Field);
// expected-warning@-1 {{Division by zero}}
// expected-note@-2 {{Division by zero}}
return false;
}
} // namespace test_break
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