r256607 - Clean up this code, NFC.

[Richard Smith via cfe-commits]

Author: rsmith
Date: Tue Dec 29 19:06:52 2015
New Revision: 256607

URL: http://llvm.org/viewvc/llvm-project?rev=256607&view=rev
Log:
Clean up this code, NFC.

Modified:
    cfe/trunk/lib/Sema/SemaChecking.cpp

Modified: cfe/trunk/lib/Sema/SemaChecking.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaChecking.cpp?rev=256607&r1=256606&r2=256607&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaChecking.cpp (original)
+++ cfe/trunk/lib/Sema/SemaChecking.cpp Tue Dec 29 19:06:52 2015
@@ -7305,20 +7305,24 @@ void CheckImplicitConversion(Sema &S, Ex
       }
     }
 
-    // If the target is bool, warn if expr is a function or method call.
-    if (Target->isSpecificBuiltinType(BuiltinType::Bool) &&
-        isa<CallExpr>(E)) {
+    // Detect the case where a call result is converted from floating-point to
+    // to bool, and the final argument to the call is converted from bool, to
+    // discover this typo:
+    //
+    //    bool b = fabs(x < 1.0);  // should be "bool b = fabs(x) < 1.0;"
+    //
+    // FIXME: This is an incredibly special case; is there some more general
+    // way to detect this class of misplaced-parentheses bug?
+    if (Target->isBooleanType() && isa<CallExpr>(E)) {
       // Check last argument of function call to see if it is an
       // implicit cast from a type matching the type the result
       // is being cast to.
       CallExpr *CEx = cast<CallExpr>(E);
-      unsigned NumArgs = CEx->getNumArgs();
-      if (NumArgs > 0) {
+      if (unsigned NumArgs = CEx->getNumArgs()) {
         Expr *LastA = CEx->getArg(NumArgs - 1);
         Expr *InnerE = LastA->IgnoreParenImpCasts();
-        const Type *InnerType =
-          S.Context.getCanonicalType(InnerE->getType()).getTypePtr();
-        if (isa<ImplicitCastExpr>(LastA) && (InnerType == Target)) {
+        if (isa<ImplicitCastExpr>(LastA) &&
+            InnerE->getType()->isBooleanType()) {
           // Warn on this floating-point to bool conversion
           DiagnoseImpCast(S, E, T, CC,
                           diag::warn_impcast_floating_point_to_bool);