r267054 - Split interesting warnings off from -Wfloat-conversion
Richard Trieu via cfe-commits
cfe-commits at lists.llvm.org
Fri Apr 22 14:08:49 PDT 2016
Nico,
With this warning, I was attempting to catch different cases of floating to
bool conversion:
bool x = 5.0; // Wrong type
void test(bool, float);
test(5.0, true); // Switched arguments.
I did not see anything like your example come up. See as there are many
edge cases in with floating point to bool conversions, I will be reverting
the bool portions of this change and following up with a different thread
to discuss how to handle the bool conversions.
-Wfloat-* are subgroups of -Wfloat-conversion which is a subgroup of
-Wconversion.
Richard
On Fri, Apr 22, 2016 at 7:41 AM, Nico Weber <thakis at chromium.org> wrote:
> Hi Richard,
>
> 1.) Are these new warnings in -Wconversion? If not, they probably should
> be, right?
>
> 2.) It looks like -Wfloat-bool-constant-conversion is on by default and
> warns on things like
>
> if (kHotspotRadius)
>
> if kHotspotRadius is a float. Do you have data that suggests that this is
> a common buggy pattern? Omitting `!= 0` is extremely common in practice,
> and it's even dictated in some style guides (e.g.
> https://webkit.org/code-style-guidelines/#null-false-and-zero ("Tests for
> [...] zero/non-zero should all be done without equality comparisons."). So
> making this a warning for floats but not for others seems weird to me.
>
> Nico
>
>
> On Thu, Apr 21, 2016 at 5:04 PM, Richard Trieu via cfe-commits <
> cfe-commits at lists.llvm.org> wrote:
>
>> Author: rtrieu
>> Date: Thu Apr 21 16:04:55 2016
>> New Revision: 267054
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=267054&view=rev
>> Log:
>> Split interesting warnings off from -Wfloat-conversion
>>
>> Restructure the implict floating point to integer conversions so that
>> interesting sub-groups are under different flags. Breakdown of warnings:
>>
>> No warning:
>> Exact conversions from floating point to integer:
>> int x = 10.0;
>> int x = 1e10;
>>
>> -Wliteral-conversion - Floating point literal to integer with rounding:
>> int x = 5.5;
>> int x = -3.4;
>>
>> -Wfloat-conversion - All conversions not covered by the above two:
>> int x = GetFloat();
>> int x = 5.5 + 3.5;
>>
>> -Wfloat-zero-conversion - The expression converted has a non-zero floating
>> point value that gets converted to a zero integer value, excluded the
>> cases
>> falling under -Wliteral-conversion. Subset of -Wfloat-conversion.
>> int x = 1.0 / 2.0;
>>
>> -Wfloat-overflow-conversion - The floating point value is outside the
>> range
>> of the integer type, exluding cases from -Wliteral conversion. Subset of
>> -Wfloat-conversion.
>> char x = 500;
>> char x = -1000;
>>
>> -Wfloat-bool-conversion - Any conversion of a floating point type to bool.
>> Subset of -Wfloat-conversion.
>> if (GetFloat()) {}
>> bool x = 5.0;
>>
>> -Wfloat-bool-constant-conversion - Conversion of a compile time
>> evaluatable
>> floating point value to bool. Subset of -Wfloat-bool-conversion.
>> bool x = 1.0;
>> bool x = 4.0 / 20.0;
>>
>> Also add EvaluateAsFloat to Sema, which is similar to EvaluateAsInt, but
>> for
>> floating point values.
>>
>>
>> Modified:
>> cfe/trunk/include/clang/AST/Expr.h
>> cfe/trunk/include/clang/Basic/DiagnosticGroups.td
>> cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
>> cfe/trunk/lib/AST/ExprConstant.cpp
>> cfe/trunk/lib/Sema/SemaChecking.cpp
>> cfe/trunk/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp
>> cfe/trunk/test/SemaCXX/warn-float-conversion.cpp
>> cfe/trunk/test/SemaCXX/warn-literal-conversion.cpp
>>
>> Modified: cfe/trunk/include/clang/AST/Expr.h
>> URL:
>> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/Expr.h?rev=267054&r1=267053&r2=267054&view=diff
>>
>> ==============================================================================
>> --- cfe/trunk/include/clang/AST/Expr.h (original)
>> +++ cfe/trunk/include/clang/AST/Expr.h Thu Apr 21 16:04:55 2016
>> @@ -594,6 +594,13 @@ public:
>> bool EvaluateAsInt(llvm::APSInt &Result, const ASTContext &Ctx,
>> SideEffectsKind AllowSideEffects =
>> SE_NoSideEffects) const;
>>
>> + /// EvaluateAsFloat - Return true if this is a constant which we can
>> fold and
>> + /// convert to a floating point value, using any crazy technique that
>> we
>> + /// want to.
>> + bool
>> + EvaluateAsFloat(llvm::APFloat &Result, const ASTContext &Ctx,
>> + SideEffectsKind AllowSideEffects = SE_NoSideEffects)
>> const;
>> +
>> /// isEvaluatable - Call EvaluateAsRValue to see if this expression
>> can be
>> /// constant folded without side-effects, but discard the result.
>> bool isEvaluatable(const ASTContext &Ctx,
>>
>> Modified: cfe/trunk/include/clang/Basic/DiagnosticGroups.td
>> URL:
>> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticGroups.td?rev=267054&r1=267053&r2=267054&view=diff
>>
>> ==============================================================================
>> --- cfe/trunk/include/clang/Basic/DiagnosticGroups.td (original)
>> +++ cfe/trunk/include/clang/Basic/DiagnosticGroups.td Thu Apr 21 16:04:55
>> 2016
>> @@ -46,7 +46,17 @@ def BoolConversion : DiagGroup<"bool-con
>>
>> UndefinedBoolConversion]>;
>> def IntConversion : DiagGroup<"int-conversion">;
>> def EnumConversion : DiagGroup<"enum-conversion">;
>> -def FloatConversion : DiagGroup<"float-conversion">;
>> +
>> +def FloatOverflowConversion : DiagGroup<"float-overflow-conversion">;
>> +def FloatZeroConversion : DiagGroup<"float-zero-conversion">;
>> +def FloatBoolConstantConversion :
>> DiagGroup<"float-bool-constant-conversion">;
>> +def FloatBoolConversion :
>> + DiagGroup<"float-bool-conversion", [FloatBoolConstantConversion]>;
>> +def FloatConversion :
>> + DiagGroup<"float-conversion", [FloatBoolConversion,
>> + FloatOverflowConversion,
>> + FloatZeroConversion]>;
>> +
>> def DoublePromotion : DiagGroup<"double-promotion">;
>> def EnumTooLarge : DiagGroup<"enum-too-large">;
>> def UnsupportedNan : DiagGroup<"unsupported-nan">;
>>
>> Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
>> URL:
>> http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=267054&r1=267053&r2=267054&view=diff
>>
>> ==============================================================================
>> --- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td (original)
>> +++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td Thu Apr 21
>> 16:04:55 2016
>> @@ -2742,9 +2742,6 @@ def warn_impcast_float_precision : Warni
>> def warn_impcast_double_promotion : Warning<
>> "implicit conversion increases floating-point precision: %0 to %1">,
>> InGroup<DoublePromotion>, DefaultIgnore;
>> -def warn_impcast_float_integer : Warning<
>> - "implicit conversion turns floating-point number into integer: %0 to
>> %1">,
>> - InGroup<FloatConversion>, DefaultIgnore;
>> def warn_impcast_integer_sign : Warning<
>> "implicit conversion changes signedness: %0 to %1">,
>> InGroup<SignConversion>, DefaultIgnore;
>> @@ -2763,9 +2760,29 @@ def warn_impcast_integer_precision_const
>> def warn_impcast_bitfield_precision_constant : Warning<
>> "implicit truncation from %2 to bitfield changes value from %0 to %1">,
>> InGroup<BitFieldConstantConversion>;
>> +
>> def warn_impcast_literal_float_to_integer : Warning<
>> "implicit conversion from %0 to %1 changes value from %2 to %3">,
>> InGroup<LiteralConversion>;
>> +def warn_impcast_float_integer : Warning<
>> + "implicit conversion turns floating-point number into integer: %0 to
>> %1">,
>> + InGroup<FloatConversion>, DefaultIgnore;
>> +
>> +def warn_impcast_float_bool : Warning<
>> + "implicit conversion turns floating-point number into boolean: %0 to
>> %1">,
>> + InGroup<FloatBoolConversion>, DefaultIgnore;
>> +def warn_impcast_float_to_bool : Warning<
>> + "implicit conversion from %0 to %1 changes value from %2 to %3">,
>> + InGroup<FloatBoolConstantConversion>;
>> +
>> +def warn_impcast_float_to_integer : Warning<
>> + "implicit conversion of out of range value from %0 to %1 changes value
>> "
>> + "from %2 to %3">,
>> + InGroup<FloatOverflowConversion>, DefaultIgnore;
>> +def warn_impcast_float_to_integer_zero : Warning<
>> + "implicit conversion from %0 to %1 changes non-zero value from %2 to
>> %3">,
>> + InGroup<FloatZeroConversion>, DefaultIgnore;
>> +
>> def warn_impcast_string_literal_to_bool : Warning<
>> "implicit conversion turns string literal into bool: %0 to %1">,
>> InGroup<StringConversion>, DefaultIgnore;
>>
>> Modified: cfe/trunk/lib/AST/ExprConstant.cpp
>> URL:
>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ExprConstant.cpp?rev=267054&r1=267053&r2=267054&view=diff
>>
>> ==============================================================================
>> --- cfe/trunk/lib/AST/ExprConstant.cpp (original)
>> +++ cfe/trunk/lib/AST/ExprConstant.cpp Thu Apr 21 16:04:55 2016
>> @@ -9027,6 +9027,20 @@ bool Expr::EvaluateAsInt(APSInt &Result,
>> return true;
>> }
>>
>> +bool Expr::EvaluateAsFloat(APFloat &Result, const ASTContext &Ctx,
>> + SideEffectsKind AllowSideEffects) const {
>> + if (!getType()->isRealFloatingType())
>> + return false;
>> +
>> + EvalResult ExprResult;
>> + if (!EvaluateAsRValue(ExprResult, Ctx) || !ExprResult.Val.isFloat() ||
>> + hasUnacceptableSideEffect(ExprResult, AllowSideEffects))
>> + return false;
>> +
>> + Result = ExprResult.Val.getFloat();
>> + return true;
>> +}
>> +
>> bool Expr::EvaluateAsLValue(EvalResult &Result, const ASTContext &Ctx)
>> const {
>> EvalInfo Info(Ctx, Result, EvalInfo::EM_ConstantFold);
>>
>>
>> Modified: cfe/trunk/lib/Sema/SemaChecking.cpp
>> URL:
>> http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaChecking.cpp?rev=267054&r1=267053&r2=267054&view=diff
>>
>> ==============================================================================
>> --- cfe/trunk/lib/Sema/SemaChecking.cpp (original)
>> +++ cfe/trunk/lib/Sema/SemaChecking.cpp Thu Apr 21 16:04:55 2016
>> @@ -7382,19 +7382,78 @@ void DiagnoseImpCast(Sema &S, Expr *E, Q
>> DiagnoseImpCast(S, E, E->getType(), T, CContext, diag,
>> pruneControlFlow);
>> }
>>
>> -/// Diagnose an implicit cast from a literal expression. Does not warn
>> when the
>> -/// cast wouldn't lose information.
>> -void DiagnoseFloatingLiteralImpCast(Sema &S, FloatingLiteral *FL,
>> QualType T,
>> - SourceLocation CContext) {
>> - // Try to convert the literal exactly to an integer. If we can, don't
>> warn.
>> +
>> +/// Diagnose an implicit cast from a floating point value to an integer
>> value.
>> +void DiagnoseFloatingImpCast(Sema &S, Expr *E, QualType T,
>> +
>> + SourceLocation CContext) {
>> + const bool IsBool = T->isSpecificBuiltinType(BuiltinType::Bool);
>> + const bool PruneWarnings = !S.ActiveTemplateInstantiations.empty();
>> +
>> + Expr *InnerE = E->IgnoreParenImpCasts();
>> + // We also want to warn on, e.g., "int i = -1.234"
>> + if (UnaryOperator *UOp = dyn_cast<UnaryOperator>(InnerE))
>> + if (UOp->getOpcode() == UO_Minus || UOp->getOpcode() == UO_Plus)
>> + InnerE = UOp->getSubExpr()->IgnoreParenImpCasts();
>> +
>> + const bool IsLiteral =
>> + isa<FloatingLiteral>(E) || isa<FloatingLiteral>(InnerE);
>> +
>> + llvm::APFloat Value(0.0);
>> + bool IsConstant =
>> + E->EvaluateAsFloat(Value, S.Context, Expr::SE_AllowSideEffects);
>> + if (!IsConstant) {
>> + if (IsBool) {
>> + return DiagnoseImpCast(S, E, T, CContext,
>> diag::warn_impcast_float_bool,
>> + PruneWarnings);
>> + } else {
>> + return DiagnoseImpCast(S, E, T, CContext,
>> + diag::warn_impcast_float_integer,
>> PruneWarnings);
>> + }
>> + }
>> +
>> bool isExact = false;
>> - const llvm::APFloat &Value = FL->getValue();
>> +
>> llvm::APSInt IntegerValue(S.Context.getIntWidth(T),
>> T->hasUnsignedIntegerRepresentation());
>> - if (Value.convertToInteger(IntegerValue,
>> - llvm::APFloat::rmTowardZero, &isExact)
>> - == llvm::APFloat::opOK && isExact)
>> - return;
>> + if (Value.convertToInteger(IntegerValue, llvm::APFloat::rmTowardZero,
>> + &isExact) == llvm::APFloat::opOK &&
>> + isExact && !IsBool) {
>> + if (IsLiteral) return;
>> + return DiagnoseImpCast(S, E, T, CContext,
>> diag::warn_impcast_float_integer,
>> + PruneWarnings);
>> + }
>> +
>> + unsigned DiagID = 0;
>> + if (IsBool) {
>> + // Warn on all floating point to bool conversions
>> + DiagID = diag::warn_impcast_float_to_bool;
>> + } else if (IsLiteral) {
>> + // Warn on floating point literal to integer.
>> + DiagID = diag::warn_impcast_literal_float_to_integer;
>> + } else if (IntegerValue == 0) {
>> + if (Value.isZero()) { // Skip -0.0 to 0 conversion.
>> + return DiagnoseImpCast(S, E, T, CContext,
>> + diag::warn_impcast_float_integer,
>> PruneWarnings);
>> + }
>> + // Warn on non-zero to zero conversion.
>> + DiagID = diag::warn_impcast_float_to_integer_zero;
>> + } else {
>> + if (IntegerValue.isUnsigned()) {
>> + if (!IntegerValue.isMaxValue()) {
>> + return DiagnoseImpCast(S, E, T, CContext,
>> + diag::warn_impcast_float_integer,
>> PruneWarnings);
>> + }
>> + } else { // IntegerValue.isSigned()
>> + if (!IntegerValue.isMaxSignedValue() &&
>> + !IntegerValue.isMinSignedValue()) {
>> + return DiagnoseImpCast(S, E, T, CContext,
>> + diag::warn_impcast_float_integer,
>> PruneWarnings);
>> + }
>> + }
>> + // Warn on evaluatable floating point expression to integer
>> conversion.
>> + DiagID = diag::warn_impcast_float_to_integer;
>> + }
>>
>> // FIXME: Force the precision of the source value down so we don't
>> print
>> // digits which are usually useless (we don't really care here if we
>> @@ -7407,14 +7466,22 @@ void DiagnoseFloatingLiteralImpCast(Sema
>> Value.toString(PrettySourceValue, precision);
>>
>> SmallString<16> PrettyTargetValue;
>> - if (T->isSpecificBuiltinType(BuiltinType::Bool))
>> + if (IsBool)
>> PrettyTargetValue = Value.isZero() ? "false" : "true";
>> else
>> IntegerValue.toString(PrettyTargetValue);
>>
>> - S.Diag(FL->getExprLoc(), diag::warn_impcast_literal_float_to_integer)
>> - << FL->getType() << T.getUnqualifiedType() << PrettySourceValue
>> - << PrettyTargetValue << FL->getSourceRange() <<
>> SourceRange(CContext);
>> + if (PruneWarnings) {
>> + S.DiagRuntimeBehavior(E->getExprLoc(), E,
>> + S.PDiag(DiagID)
>> + << E->getType() << T.getUnqualifiedType()
>> + << PrettySourceValue << PrettyTargetValue
>> + << E->getSourceRange() <<
>> SourceRange(CContext));
>> + } else {
>> + S.Diag(E->getExprLoc(), DiagID)
>> + << E->getType() << T.getUnqualifiedType() << PrettySourceValue
>> + << PrettyTargetValue << E->getSourceRange() <<
>> SourceRange(CContext);
>> + }
>> }
>>
>> std::string PrettyPrintInRange(const llvm::APSInt &Value, IntRange
>> Range) {
>> @@ -7748,22 +7815,12 @@ void CheckImplicitConversion(Sema &S, Ex
>> return;
>> }
>>
>> - // If the target is integral, always warn.
>> + // If the target is integral, always warn.
>> if (TargetBT && TargetBT->isInteger()) {
>> if (S.SourceMgr.isInSystemMacro(CC))
>> return;
>> -
>> - Expr *InnerE = E->IgnoreParenImpCasts();
>> - // We also want to warn on, e.g., "int i = -1.234"
>> - if (UnaryOperator *UOp = dyn_cast<UnaryOperator>(InnerE))
>> - if (UOp->getOpcode() == UO_Minus || UOp->getOpcode() == UO_Plus)
>> - InnerE = UOp->getSubExpr()->IgnoreParenImpCasts();
>> -
>> - if (FloatingLiteral *FL = dyn_cast<FloatingLiteral>(InnerE)) {
>> - DiagnoseFloatingLiteralImpCast(S, FL, T, CC);
>> - } else {
>> - DiagnoseImpCast(S, E, T, CC, diag::warn_impcast_float_integer);
>> - }
>> +
>> + DiagnoseFloatingImpCast(S, E, T, CC);
>> }
>>
>> // Detect the case where a call result is converted from
>> floating-point to
>>
>> Modified: cfe/trunk/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp
>> URL:
>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp?rev=267054&r1=267053&r2=267054&view=diff
>>
>> ==============================================================================
>> --- cfe/trunk/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp
>> (original)
>> +++ cfe/trunk/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp Thu Apr
>> 21 16:04:55 2016
>> @@ -58,8 +58,8 @@ void float_to_int() {
>> Agg<char> ce1 = { Convert<float>(1.0) }; // expected-error {{type
>> 'float' cannot be narrowed to 'char'}} expected-note {{silence}}
>> Agg<char> ce2 = { ConvertVar<double>() }; // expected-error {{type
>> 'double' cannot be narrowed to 'char'}} expected-note {{silence}}
>>
>> - bool b{1.0}; // expected-error {{type 'double' cannot be narrowed to
>> 'bool'}} expected-note {{silence}}
>> - Agg<bool> ab = {0.0}; // expected-error {{type 'double' cannot be
>> narrowed to 'bool'}} expected-note {{silence}}
>> + bool b{1.0}; // expected-error {{type 'double' cannot be narrowed to
>> 'bool'}} expected-note {{silence}} expected-warning {{changes value}}
>> + Agg<bool> ab = {0.0}; // expected-error {{type 'double' cannot be
>> narrowed to 'bool'}} expected-note {{silence}} expected-warning {{changes
>> value}}
>> }
>>
>> // * from long double to double or float, or from double to float,
>> except where
>>
>> Modified: cfe/trunk/test/SemaCXX/warn-float-conversion.cpp
>> URL:
>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/warn-float-conversion.cpp?rev=267054&r1=267053&r2=267054&view=diff
>>
>> ==============================================================================
>> --- cfe/trunk/test/SemaCXX/warn-float-conversion.cpp (original)
>> +++ cfe/trunk/test/SemaCXX/warn-float-conversion.cpp Thu Apr 21 16:04:55
>> 2016
>> @@ -1,5 +1,12 @@
>> -// RUN: %clang_cc1 -verify -fsyntax-only %s -Wfloat-conversion
>> +// RUN: %clang_cc1 -verify -fsyntax-only -triple x86_64-pc-linux-gnu %s
>> -Wno-literal-conversion -Wfloat-conversion -DFLOAT_CONVERSION -DZERO -DBOOL
>> -DCONSTANT_BOOL -DOVERFLOW
>> +// RUN: %clang_cc1 -verify -fsyntax-only -triple x86_64-pc-linux-gnu %s
>> -Wno-conversion -Wfloat-overflow-conversion -DOVERFLOW
>> +// RUN: %clang_cc1 -verify -fsyntax-only -triple x86_64-pc-linux-gnu %s
>> -Wno-conversion -Wfloat-zero-conversion -DZERO
>> +// RUN: %clang_cc1 -verify -fsyntax-only -triple x86_64-pc-linux-gnu %s
>> -Wno-conversion -Wfloat-bool-constant-conversion -DCONSTANT_BOOL
>> +// RUN: %clang_cc1 -verify -fsyntax-only -triple x86_64-pc-linux-gnu %s
>> -Wno-conversion -Wfloat-bool-conversion -DCONSTANT_BOOL -DBOOL
>>
>> +float ReturnFloat();
>> +
>> +#ifdef FLOAT_CONVERSION
>> bool ReturnBool(float f) {
>> return f; //expected-warning{{conversion}}
>> }
>> @@ -36,3 +43,80 @@ void Convert(float f, double d, long dou
>> l = ld; //expected-warning{{conversion}}
>> }
>>
>> +void Test() {
>> + int a1 = 10.0/2.0; //expected-warning{{conversion}}
>> + int a2 = 1.0/2.0; //expected-warning{{conversion}}
>> + bool a3 = ReturnFloat(); //expected-warning{{conversion}}
>> + int a4 = 1e30 + 1; //expected-warning{{conversion}}
>> +}
>> +
>> +void TestConstantFloat() {
>> + // Don't warn on exact floating literals.
>> + int a1 = 5.0;
>> + int a2 = 1e3;
>> +
>> + int a3 = 5.5; // caught by -Wliteral-conversion
>> + int a4 = 500.44; // caught by -Wliteral-convserion
>> +
>> + int b1 = 5.0 / 1.0; //expected-warning{{conversion}}
>> + int b2 = 5.0 / 2.0; //expected-warning{{conversion}}
>> +
>> + const float five = 5.0;
>> +
>> + int b3 = five / 1.0; //expected-warning{{conversion}}
>> + int b4 = five / 2.0; //expected-warning{{conversion}}
>> +}
>> +#endif // FLOAT_CONVERSION
>> +
>> +#ifdef CONSTANT_BOOL
>> +const float pi = 3.1415;
>> +
>> +void TestConstantBool() {
>> + 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}}
>> + bool b3 = 0.0f; // expected-warning {{implicit conversion from 'float'
>> to 'bool' changes value from 0 to false}}
>> + bool b4 = 0.0; // expected-warning {{implicit conversion from 'double'
>> to 'bool' changes value from 0 to false}}
>> + bool b5 = 1.0f; // expected-warning {{implicit conversion from 'float'
>> to 'bool' changes value from 1 to true}}
>> + bool b6 = 1.0; // expected-warning {{implicit conversion from 'double'
>> to 'bool' changes value from 1 to true}}
>> + bool b7 = pi; // expected-warning {{implicit conversion from 'const
>> float' to 'bool' changes value from 3.1415 to true}}
>> + bool b8 = pi - pi; // expected-warning {{implicit conversion from
>> 'float' to 'bool' changes value from 0 to false}}
>> +}
>> +#endif // CONSTANT_BOOL
>> +
>> +#ifdef BOOL
>> +const float E = 2.718;
>> +
>> +float GetFloat();
>> +double GetDouble();
>> +
>> +void TestBool() {
>> + bool b1 = GetFloat(); // expected-warning {{implicit conversion turns
>> floating-point number into boolean: 'float' to 'bool'}}
>> + bool b2 = GetDouble(); // expected-warning {{implicit conversion turns
>> floating-point number into boolean: 'double' to 'bool'}}
>> + bool b3 = 0.0 * GetDouble(); // expected-warning {{implicit conversion
>> turns floating-point number into boolean: 'double' to 'bool'}}
>> + bool b4 = GetFloat() + GetDouble(); // expected-warning {{implicit
>> conversion turns floating-point number into boolean: 'double' to 'bool'}}
>> + bool b5 = E + GetFloat(); // expected-warning {{implicit conversion
>> turns floating-point number into boolean: 'float' to 'bool'}}
>> +}
>> +
>> +#endif // BOOL
>> +
>> +#ifdef ZERO
>> +void TestZero() {
>> + const float half = .5;
>> + int a1 = half; // expected-warning{{implicit conversion from 'const
>> float' to 'int' changes non-zero value from 0.5 to 0}}
>> + int a2 = 1.0 / 2.0; // expected-warning{{implicit conversion from
>> 'double' to 'int' changes non-zero value from 0.5 to 0}}
>> + int a3 = 5;
>> +}
>> +#endif // ZERO
>> +
>> +#ifdef OVERFLOW
>> +void TestOverflow() {
>> + char a = 500.0; // caught by -Wliteral-conversion
>> + char b = -500.0; // caught by -Wliteral-conversion
>> +
>> + const float LargeNumber = 1024;
>> + char c = LargeNumber; // expected-warning{{implicit conversion of out
>> of range value from 'const float' to 'char' changes value from 1024 to 127}}
>> + char d = 400.0 + 400.0; // expected-warning{{implicit conversion of
>> out of range value from 'double' to 'char' changes value from 800 to 127}}
>> +
>> + char e = 1.0 / 0.0; // expected-warning{{implicit conversion of out
>> of range value from 'double' to 'char' changes value from +Inf to 127}}
>> +}
>> +#endif // OVERFLOW
>>
>> Modified: cfe/trunk/test/SemaCXX/warn-literal-conversion.cpp
>> URL:
>> http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/warn-literal-conversion.cpp?rev=267054&r1=267053&r2=267054&view=diff
>>
>> ==============================================================================
>> --- cfe/trunk/test/SemaCXX/warn-literal-conversion.cpp (original)
>> +++ cfe/trunk/test/SemaCXX/warn-literal-conversion.cpp Thu Apr 21
>> 16:04:55 2016
>> @@ -25,7 +25,7 @@ void test0() {
>> // 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}}
>> + 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.)
>> @@ -38,14 +38,3 @@ void test0() {
>> 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;
>> -}
>>
>>
>> _______________________________________________
>> cfe-commits mailing list
>> cfe-commits at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
>>
>
>
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