[cfe-commits] r168023 - in /cfe/trunk: lib/Sema/SemaChecking.cpp test/SemaCXX/compare.cpp

[Richard Trieu]

Author: rtrieu
Date: Wed Nov 14 21:43:50 2012
New Revision: 168023

URL: http://llvm.org/viewvc/llvm-project?rev=168023&view=rev
Log:
Fix an off-by-one error by switching < to <= in -Wtautological-constant-out-of-range-compare and added test case.

Modified:
    cfe/trunk/lib/Sema/SemaChecking.cpp
    cfe/trunk/test/SemaCXX/compare.cpp

Modified: cfe/trunk/lib/Sema/SemaChecking.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaChecking.cpp?rev=168023&r1=168022&r2=168023&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaChecking.cpp (original)
+++ cfe/trunk/lib/Sema/SemaChecking.cpp Wed Nov 14 21:43:50 2012
@@ -4385,7 +4385,7 @@
       // Check to see if the constant is equivalent to a negative value
       // cast to CommonT.
       if (S.Context.getIntWidth(ConstantT) == S.Context.getIntWidth(CommonT) &&
-          Value.isNegative() && Value.getMinSignedBits() < OtherWidth)
+          Value.isNegative() && Value.getMinSignedBits() <= OtherWidth)
         return;
       // The constant value rests between values that OtherT can represent after
       // conversion.  Relational comparison still works, but equality

Modified: cfe/trunk/test/SemaCXX/compare.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/compare.cpp?rev=168023&r1=168022&r2=168023&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/compare.cpp (original)
+++ cfe/trunk/test/SemaCXX/compare.cpp Wed Nov 14 21:43:50 2012
@@ -311,6 +311,7 @@
   (void)((int)other != (unsigned long)(0x00000000ffffffff)); // expected-warning{{true}}
   (void)((int)other != (unsigned long)(0x000000000fffffff));
   (void)((int)other < (unsigned long)(0x00000000ffffffff));  // expected-warning{{different signs}}
+  (void)((int)other == (unsigned)(0x800000000));
 
   // Common unsigned, other unsigned, constant signed
   (void)((unsigned long)other != (int)(0xffffffff));  // expected-warning{{different signs}}