From: Richard Smith <richard-llvm@metafoo.co.uk>
Date: Thu, 19 Feb 2015 00:39:05 +0000 (+0000)
Subject: PR22566: a conversion from a floating-point type to bool is a narrowing conversion.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=6443e006c6a93a8eb0d8a1ab8c0a5cbe248b98cc;p=clang

PR22566: a conversion from a floating-point type to bool is a narrowing conversion.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@229792 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index 53ebdd793b..0728f783aa 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -286,6 +286,16 @@ StandardConversionSequence::getNarrowingKind(ASTContext &Ctx,
   QualType FromType = getToType(0);
   QualType ToType = getToType(1);
   switch (Second) {
+  // 'bool' is an integral type; dispatch to the right place to handle it.
+  case ICK_Boolean_Conversion:
+    if (FromType->isRealFloatingType())
+      goto FloatingIntegralConversion;
+    if (FromType->isIntegralOrUnscopedEnumerationType())
+      goto IntegralConversion;
+    // Boolean conversions can be from pointers and pointers to members
+    // [conv.bool], and those aren't considered narrowing conversions.
+    return NK_Not_Narrowing;
+
   // -- from a floating-point type to an integer type, or
   //
   // -- from an integer type or unscoped enumeration type to a floating-point
@@ -293,6 +303,7 @@ StandardConversionSequence::getNarrowingKind(ASTContext &Ctx,
   //    value after conversion will fit into the target type and will produce
   //    the original value when converted back to the original type, or
   case ICK_Floating_Integral:
+  FloatingIntegralConversion:
     if (FromType->isRealFloatingType() && ToType->isIntegralType(Ctx)) {
       return NK_Type_Narrowing;
     } else if (FromType->isIntegralType(Ctx) && ToType->isRealFloatingType()) {
@@ -357,13 +368,8 @@ StandardConversionSequence::getNarrowingKind(ASTContext &Ctx,
   //    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.
-  case ICK_Boolean_Conversion:  // Bools are integers too.
-    if (!FromType->isIntegralOrUnscopedEnumerationType()) {
-      // Boolean conversions can be from pointers and pointers to members
-      // [conv.bool], and those aren't considered narrowing conversions.
-      return NK_Not_Narrowing;
-    }  // Otherwise, fall through to the integral case.
-  case ICK_Integral_Conversion: {
+  case ICK_Integral_Conversion:
+  IntegralConversion: {
     assert(FromType->isIntegralOrUnscopedEnumerationType());
     assert(ToType->isIntegralOrUnscopedEnumerationType());
     const bool FromSigned = FromType->isSignedIntegerOrEnumerationType();
diff --git a/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp b/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp
index 42dee92b3c..48c5b23207 100644
--- a/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp
+++ b/test/CXX/dcl.decl/dcl.init/dcl.init.list/p7-0x.cpp
@@ -57,6 +57,9 @@ 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}}
 }
 
 // * from long double to double or float, or from double to float, except where