r192673 - Special case '%C' handling in ObjC format strings to handle integer literals that can represent unicode characters

[Ted Kremenek]

Author: kremenek
Date: Tue Oct 15 00:25:17 2013
New Revision: 192673

URL: http://llvm.org/viewvc/llvm-project?rev=192673&view=rev
Log:
Special case '%C' handling in ObjC format strings to handle integer literals that can represent unicode characters

Fixes <rdar://problem/13991617>.

Modified:
    cfe/trunk/lib/Sema/SemaChecking.cpp
    cfe/trunk/test/FixIt/format.m
    cfe/trunk/test/FixIt/format.mm
    cfe/trunk/test/SemaObjC/format-strings-objc.m

Modified: cfe/trunk/lib/Sema/SemaChecking.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaChecking.cpp?rev=192673&r1=192672&r2=192673&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaChecking.cpp (original)
+++ cfe/trunk/lib/Sema/SemaChecking.cpp Tue Oct 15 00:25:17 2013
@@ -3115,7 +3115,15 @@ CheckPrintfHandler::checkFormatExpr(cons
       // 'unichar' is defined as a typedef of unsigned short, but we should
       // prefer using the typedef if it is visible.
       IntendedTy = S.Context.UnsignedShortTy;
-      
+
+      // While we are here, check if the value is an IntegerLiteral that happens
+      // to be within the valid range.
+      if (const IntegerLiteral *IL = dyn_cast<IntegerLiteral>(E)) {
+        const llvm::APInt &V = IL->getValue();
+        if (V.getActiveBits() <= S.Context.getTypeSize(IntendedTy))
+          return true;
+      }
+
       LookupResult Result(S, &S.Context.Idents.get("unichar"), E->getLocStart(),
                           Sema::LookupOrdinaryName);
       if (S.LookupName(Result, S.getCurScope())) {

Modified: cfe/trunk/test/FixIt/format.m
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/FixIt/format.m?rev=192673&r1=192672&r2=192673&view=diff
==============================================================================
--- cfe/trunk/test/FixIt/format.m (original)
+++ cfe/trunk/test/FixIt/format.m Tue Oct 15 00:25:17 2013
@@ -186,26 +186,26 @@ void test_percent_C() {
   const unsigned short data = 'a';
   NSLog(@"%C", data);  // no-warning
 
-  NSLog(@"%C", 0x2603);  // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'int'}}
+  NSLog(@"%C", 0x260300);  // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'int'}}
   // CHECK-NOT: fix-it:"{{.*}}":{[[@LINE-1]]:11-[[@LINE-1]]:13}:"%d"
   // CHECK: fix-it:"{{.*}}":{[[@LINE-2]]:16-[[@LINE-2]]:16}:"(unsigned short)"
 
   typedef unsigned short unichar;
   
-  NSLog(@"%C", 0x2603);  // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'int'}}
+  NSLog(@"%C", 0x260300);  // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'int'}}
   // CHECK-NOT: fix-it:"{{.*}}":{[[@LINE-1]]:11-[[@LINE-1]]:13}:"%d"
   // CHECK: fix-it:"{{.*}}":{[[@LINE-2]]:16-[[@LINE-2]]:16}:"(unichar)"
   
-  NSLog(@"%C", data ? 0x2F : 0x2603); // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'int'}}
+  NSLog(@"%C", data ? 0x2F0000 : 0x260300); // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'int'}}
   // CHECK-NOT: fix-it:"{{.*}}":{[[@LINE-1]]:11-[[@LINE-1]]:13}:"%d"
   // CHECK: fix-it:"{{.*}}":{[[@LINE-2]]:16-[[@LINE-2]]:16}:"(unichar)("
-  // CHECK: fix-it:"{{.*}}":{[[@LINE-3]]:36-[[@LINE-3]]:36}:")"
+  // CHECK: fix-it:"{{.*}}":{[[@LINE-3]]:42-[[@LINE-3]]:42}:")"
 
   NSLog(@"%C", 0.0); // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'double'}}
   // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:11-[[@LINE-1]]:13}:"%f"
   // CHECK-NOT: fix-it:"{{.*}}":{[[@LINE-2]]:16-[[@LINE-2]]:16}:"(unichar)"
 
-  NSLog(@"%C", (char)0x2603); // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'char'}}
+  NSLog(@"%C", (char)0x260300); // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'char'}}
   // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:11-[[@LINE-1]]:13}:"%c"
   // CHECK-NOT: fix-it:"{{.*}}":{[[@LINE-2]]:16-[[@LINE-2]]:22}:"(unichar)"
 

Modified: cfe/trunk/test/FixIt/format.mm
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/FixIt/format.mm?rev=192673&r1=192672&r2=192673&view=diff
==============================================================================
--- cfe/trunk/test/FixIt/format.mm (original)
+++ cfe/trunk/test/FixIt/format.mm Tue Oct 15 00:25:17 2013
@@ -11,7 +11,7 @@ void test_percent_C() {
   NSLog(@"%C", wchar_data);  // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'wchar_t'}}
   // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:16-[[@LINE-1]]:16}:"(unsigned short)"
 
-  NSLog(@"%C", 0x2603);  // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'int'}}
+  NSLog(@"%C", 0x260300);  // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'int'}}
   // CHECK-NOT: fix-it:"{{.*}}":{[[@LINE-1]]:11-[[@LINE-1]]:13}:"%d"
   // CHECK: fix-it:"{{.*}}":{[[@LINE-2]]:16-[[@LINE-2]]:16}:"(unsigned short)"
 
@@ -20,7 +20,7 @@ void test_percent_C() {
   NSLog(@"%C", wchar_data);  // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'wchar_t'}}
   // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:16-[[@LINE-1]]:16}:"(unichar)"
   
-  NSLog(@"%C", 0x2603);  // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'int'}}
+  NSLog(@"%C", 0x260300);  // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'int'}}
   // CHECK-NOT: fix-it:"{{.*}}":{[[@LINE-1]]:11-[[@LINE-1]]:13}:"%d"
   // CHECK: fix-it:"{{.*}}":{[[@LINE-2]]:16-[[@LINE-2]]:16}:"(unichar)"
   

Modified: cfe/trunk/test/SemaObjC/format-strings-objc.m
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaObjC/format-strings-objc.m?rev=192673&r1=192672&r2=192673&view=diff
==============================================================================
--- cfe/trunk/test/SemaObjC/format-strings-objc.m (original)
+++ cfe/trunk/test/SemaObjC/format-strings-objc.m Tue Oct 15 00:25:17 2013
@@ -243,3 +243,8 @@ void testTypeOf(NSInteger dW, NSInteger
   NSLog(@"dW %d  dH %d",({ __typeof__(dW) __a = (dW); __a < 0 ? -__a : __a; }),({ __typeof__(dH) __a = (dH); __a < 0 ? -__a : __a; })); // expected-warning 2 {{values of type 'NSInteger' should not be used as format arguments; add an explicit cast to 'long' instead}}
 }
 
+void testUnicode() {
+  NSLog(@"%C", 0x2022); // no-warning
+  NSLog(@"%C", 0x202200); // expected-warning{{format specifies type 'unichar' (aka 'unsigned short') but the argument has type 'int'}}
+}
+