llvm-project/clang/test/SemaCXX/warn-literal-conversion.cpp

52 lines
2.7 KiB
C++

// RUN: %clang_cc1 -fsyntax-only -Wliteral-conversion -verify %s
void foo(int y);
// Warn when a literal float or double is assigned or bound to an integer.
void test0() {
// Float
int y0 = 1.2222F; // expected-warning {{implicit conversion from 'float' to 'int' changes value from 1.2222 to 1}}
int y1 = (1.2222F); // expected-warning {{implicit conversion from 'float' to 'int' changes value from 1.2222 to 1}}
int y2 = (((1.2222F))); // expected-warning {{implicit conversion from 'float' to 'int' changes value from 1.2222 to 1}}
int y3 = 12E-1F; // expected-warning {{implicit conversion from 'float' to 'int' changes value from 1.2 to 1}}
int y4 = 1.23E1F; // expected-warning {{implicit conversion from 'float' to 'int' changes value from 12.3 to 12}}
// Double
int y5 = 1.2222; // expected-warning {{implicit conversion from 'double' to 'int' changes value from 1.2222 to 1}}
int y6 = 12E-1; // expected-warning {{implicit conversion from 'double' to 'int' changes value from 1.2 to 1}}
int y7 = 1.23E1; // expected-warning {{implicit conversion from 'double' to 'int' changes value from 12.3 to 12}}
int y8 = (1.23E1); // expected-warning {{implicit conversion from 'double' to 'int' changes value from 12.3 to 12}}
// Test assignment to an existing variable.
y8 = 2.22F; // expected-warning {{implicit conversion from 'float' to 'int' changes value from 2.22 to 2}}
// Test direct initialization.
int y9(1.23F); // expected-warning {{implicit conversion from 'float' to 'int' changes value from 1.23 to 1}}
// Test passing a literal floating-point value to a function that takes an integer.
foo(1.2F); // expected-warning {{implicit conversion from 'float' to 'int' changes value from 1.2 to 1}}
int y10 = -1.2F; // expected-warning {{implicit conversion from 'float' to 'int' changes value from -1.2 to -1}}
// -Wliteral-conversion does NOT catch const values.
// (-Wconversion DOES catch them.)
static const float sales_tax_rate = .095F;
int z = sales_tax_rate;
foo(sales_tax_rate);
// Expressions, such as those that indicate rounding-down, should NOT produce warnings.
int x = 24 * 0.5;
int y = (24*60*60) * 0.25;
int pennies = 123.45 * 100;
}
// Similarly, test floating point conversion to bool. Only float values of zero
// are converted to false; everything else is converted to true.
void test1() {
bool b1 = 0.99f; // expected-warning {{implicit conversion from 'float' to 'bool' changes value from 0.99 to true}}
bool b2 = 0.99; // expected-warning {{implicit conversion from 'double' to 'bool' changes value from 0.99 to true}}
// These do not warn because they can be directly converted to integral
// values.
bool b3 = 0.0f;
bool b4 = 0.0;
}