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Diffstat (limited to 'clang/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp')
| -rw-r--r-- | clang/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/clang/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp b/clang/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp new file mode 100644 index 0000000..db20ea6 --- /dev/null +++ b/clang/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp @@ -0,0 +1,209 @@ +// RUN: %clang_cc1 -fsyntax-only -std=c++11 -triple x86_64-apple-macosx10.6.7 -verify %s + +// Verify that narrowing conversions in initializer lists cause errors in C++0x +// mode. + +void std_example() { + int x = 999; // x is not a constant expression + const int y = 999; + const int z = 99; + char c1 = x; // OK, though it might narrow (in this case, it does narrow) + char c2{x}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + char c3{y}; // expected-error {{ cannot be narrowed }} expected-note {{override}} expected-warning {{changes value}} + char c4{z}; // OK: no narrowing needed + unsigned char uc1 = {5}; // OK: no narrowing needed + unsigned char uc2 = {-1}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + unsigned int ui1 = {-1}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + signed int si1 = + { (unsigned int)-1 }; // expected-error {{ cannot be narrowed }} expected-note {{override}} + int ii = {2.0}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + float f1 { x }; // expected-error {{ cannot be narrowed }} expected-note {{override}} + float f2 { 7 }; // OK: 7 can be exactly represented as a float + int f(int); + int a[] = + { 2, f(2), f(2.0) }; // OK: the double-to-int conversion is not at the top level +} + +// Test each rule individually. + +template<typename T> +struct Agg { + T t; +}; + +template<typename T> +struct Convert { + constexpr Convert(T v) : v(v) {} + constexpr operator T() const { return v; } + T v; +}; +template<typename T> Convert<T> ConvertVar(); + +// C++0x [dcl.init.list]p7: A narrowing conversion is an implicit conversion +// +// * from a floating-point type to an integer type, or + +void float_to_int() { + Agg<char> a1 = {1.0F}; // expected-error {{type 'float' cannot be narrowed to 'char'}} expected-note {{override}} + Agg<char> a2 = {1.0}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + Agg<char> a3 = {1.0L}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + + float f = 1.0; + double d = 1.0; + long double ld = 1.0; + Agg<char> a4 = {f}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + Agg<char> a5 = {d}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + Agg<char> a6 = {ld}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + + Agg<char> ce1 = { Convert<float>(1.0) }; // expected-error {{type 'float' cannot be narrowed to 'char'}} expected-note {{override}} + Agg<char> ce2 = { ConvertVar<double>() }; // expected-error {{type 'double' cannot be narrowed to 'char'}} expected-note {{override}} +} + +// * from long double to double or float, or from double to float, except where +// the source is a constant expression and the actual value after conversion +// is within the range of values that can be represented (even if it cannot be +// represented exactly), or + +void shrink_float() { + // These aren't constant expressions. + float f = 1.0; + double d = 1.0; + long double ld = 1.0; + + // Variables. + Agg<float> f1 = {f}; // OK (no-op) + Agg<float> f2 = {d}; // expected-error {{non-constant-expression cannot be narrowed from type 'double' to 'float'}} expected-note {{override}} + Agg<float> f3 = {ld}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + // Exact constants. + Agg<float> f4 = {1.0}; // OK (double constant represented exactly) + Agg<float> f5 = {1.0L}; // OK (long double constant represented exactly) + // Inexact but in-range constants. + Agg<float> f6 = {0.1}; // OK (double constant in range but rounded) + Agg<float> f7 = {0.1L}; // OK (long double constant in range but rounded) + // Out of range constants. + Agg<float> f8 = {1E50}; // expected-error {{constant expression evaluates to 1.000000e+50 which cannot be narrowed to type 'float'}} expected-note {{override}} + Agg<float> f9 = {1E50L}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + // More complex constant expression. + constexpr long double e40 = 1E40L, e30 = 1E30L, e39 = 1E39L; + Agg<float> f10 = {e40 - 5 * e39 + e30 - 5 * e39}; // OK + + // Variables. + Agg<double> d1 = {f}; // OK (widening) + Agg<double> d2 = {d}; // OK (no-op) + Agg<double> d3 = {ld}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + // Exact constant. + Agg<double> d4 = {1.0L}; // OK (long double constant represented exactly) + // Inexact but in-range constant. + Agg<double> d5 = {0.1L}; // OK (long double constant in range but rounded) + // Out of range constant. + Agg<double> d6 = {1E315L}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + // More complex constant expression. + constexpr long double e315 = 1E315L, e305 = 1E305L, e314 = 1E314L; + Agg<double> d7 = {e315 - 5 * e314 + e305 - 5 * e314}; // OK + + Agg<float> ce1 = { Convert<double>(1e300) }; // expected-error {{constant expression evaluates to 1.000000e+300 which cannot be narrowed to type 'float'}} expected-note {{override}} + Agg<double> ce2 = { ConvertVar<long double>() }; // expected-error {{non-constant-expression cannot be narrowed from type 'long double' to 'double'}} expected-note {{override}} +} + +// * from an integer type or unscoped enumeration type to a floating-point type, +// except where the source is a constant expression and the actual value after +// conversion will fit into the target type and will produce the original +// value when converted back to the original type, or +void int_to_float() { + // Not a constant expression. + char c = 1; + + // Variables. Yes, even though all char's will fit into any floating type. + Agg<float> f1 = {c}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + Agg<double> f2 = {c}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + Agg<long double> f3 = {c}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + + // Constants. + Agg<float> f4 = {12345678}; // OK (exactly fits in a float) + Agg<float> f5 = {123456789}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + + Agg<float> ce1 = { Convert<int>(123456789) }; // expected-error {{constant expression evaluates to 123456789 which cannot be narrowed to type 'float'}} expected-note {{override}} + Agg<double> ce2 = { ConvertVar<long long>() }; // expected-error {{non-constant-expression cannot be narrowed from type 'long long' to 'double'}} expected-note {{override}} +} + +// * from an integer type or unscoped enumeration type to an integer type that +// cannot represent all the values of the original type, except where the +// source is a constant expression and the actual value after conversion will +// fit into the target type and will produce the original value when converted +// back to the original type. +void shrink_int() { + // Not a constant expression. + short s = 1; + unsigned short us = 1; + Agg<char> c1 = {s}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + Agg<unsigned short> s1 = {s}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + Agg<short> s2 = {us}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + + // "that cannot represent all the values of the original type" means that the + // validity of the program depends on the relative sizes of integral types. + // This test compiles with -m64, so sizeof(int)<sizeof(long)==sizeof(long + // long). + long l1 = 1; + Agg<int> i1 = {l1}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + long long ll = 1; + Agg<long> l2 = {ll}; // OK + + // Constants. + Agg<char> c2 = {127}; // OK + Agg<char> c3 = {300}; // expected-error {{ cannot be narrowed }} expected-note {{override}} expected-warning {{changes value}} + + Agg<int> i2 = {0x7FFFFFFFU}; // OK + Agg<int> i3 = {0x80000000U}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + Agg<unsigned int> i4 = {-0x80000000L}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + + // Bool is also an integer type, but conversions to it are a different AST + // node. + Agg<bool> b1 = {0}; // OK + Agg<bool> b2 = {1}; // OK + Agg<bool> b3 = {-1}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + + // Conversions from pointers to booleans aren't narrowing conversions. + Agg<bool> b = {&b1}; // OK + + Agg<short> ce1 = { Convert<int>(100000) }; // expected-error {{constant expression evaluates to 100000 which cannot be narrowed to type 'short'}} expected-note {{override}} expected-warning {{changes value from 100000 to -31072}} + Agg<char> ce2 = { ConvertVar<short>() }; // expected-error {{non-constant-expression cannot be narrowed from type 'short' to 'char'}} expected-note {{override}} +} + +// Be sure that type- and value-dependent expressions in templates get the error +// too. + +template<int I, typename T> +void maybe_shrink_int(T t) { + Agg<short> s1 = {t}; // expected-error {{ cannot be narrowed }} expected-note {{override}} + Agg<short> s2 = {I}; // expected-error {{ cannot be narrowed }} expected-note {{override}} expected-warning {{changes value}} + Agg<T> t2 = {700}; // expected-error {{ cannot be narrowed }} expected-note {{override}} expected-warning {{changes value}} +} + +void test_template() { + maybe_shrink_int<15>((int)3); // expected-note {{in instantiation}} + maybe_shrink_int<70000>((char)3); // expected-note {{in instantiation}} +} + + +// We don't want qualifiers on the types in the diagnostic. + +void test_qualifiers(int i) { + const int j = i; + struct {const unsigned char c;} c1 = {j}; // expected-error {{from type 'int' to 'unsigned char' in}} expected-note {{override}} + // Template arguments make it harder to avoid printing qualifiers: + Agg<const unsigned char> c2 = {j}; // expected-error {{from type 'int' to 'const unsigned char' in}} expected-note {{override}} +} + +// Test SFINAE checks. +template<unsigned> struct Value { }; + +template<typename T> +int &check_narrowed(Value<sizeof((T){1.1})>); + +template<typename T> +float &check_narrowed(...); + +void test_narrowed(Value<sizeof(int)> vi, Value<sizeof(double)> vd) { + int &ir = check_narrowed<double>(vd); + float &fr = check_narrowed<int>(vi); +} |