Parse 'technical term' format specifier.

Objective-C format strings now support modifier flags
that can be attached to a '@' conversion.  Currently
the only one supported, as of iOS 9 and OS X 10.11,
is the new "technical term", denoted by the flag "tt",
for example:

  %[tt]@

instead of just:

  %@

The 'tt' stands for "technical term", which is used
by the string-localization facilities on Darwin to
add the appropriate spacing or quotation depending
the language locale.

Implements <rdar://problem/20374720>.

llvm-svn: 241243

1 files changed, 46 insertions, 1 deletions

diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index 870da782b97..5737e8338ff 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -3572,8 +3572,18 @@ public:
                          const char *startSpecifier, unsigned specifierLen);
   bool checkForCStrMembers(const analyze_printf::ArgType &AT,
                            const Expr *E);
+                           
+  void HandleEmptyObjCModifierFlag(const char *startFlag,
+                                   unsigned flagLen) override;
 
-};  
+  void HandleInvalidObjCModifierFlag(const char *startFlag,
+                                            unsigned flagLen) override;
+
+  void HandleObjCFlagsWithNonObjCConversion(const char *flagsStart,
+                                           const char *flagsEnd,
+                                           const char *conversionPosition) 
+                                             override;
+};
 }
 
 bool CheckPrintfHandler::HandleInvalidPrintfConversionSpecifier(
@@ -3693,6 +3703,41 @@ void CheckPrintfHandler::HandleIgnoredFlag(
                          getSpecifierRange(ignoredFlag.getPosition(), 1)));
 }
 
+//  void EmitFormatDiagnostic(PartialDiagnostic PDiag, SourceLocation StringLoc,
+//                            bool IsStringLocation, Range StringRange,
+//                            ArrayRef<FixItHint> Fixit = None);
+                            
+void CheckPrintfHandler::HandleEmptyObjCModifierFlag(const char *startFlag,
+                                                     unsigned flagLen) {
+  // Warn about an empty flag.
+  EmitFormatDiagnostic(S.PDiag(diag::warn_printf_empty_objc_flag),
+                       getLocationOfByte(startFlag),
+                       /*IsStringLocation*/true,
+                       getSpecifierRange(startFlag, flagLen));
+}
+
+void CheckPrintfHandler::HandleInvalidObjCModifierFlag(const char *startFlag,
+                                                       unsigned flagLen) {
+  // Warn about an invalid flag.
+  auto Range = getSpecifierRange(startFlag, flagLen);
+  StringRef flag(startFlag, flagLen);
+  EmitFormatDiagnostic(S.PDiag(diag::warn_printf_invalid_objc_flag) << flag,
+                      getLocationOfByte(startFlag),
+                      /*IsStringLocation*/true,
+                      Range, FixItHint::CreateRemoval(Range));
+}
+
+void CheckPrintfHandler::HandleObjCFlagsWithNonObjCConversion(
+    const char *flagsStart, const char *flagsEnd, const char *conversionPosition) {
+    // Warn about using '[...]' without a '@' conversion.
+    auto Range = getSpecifierRange(flagsStart, flagsEnd - flagsStart + 1);
+    auto diag = diag::warn_printf_ObjCflags_without_ObjCConversion;
+    EmitFormatDiagnostic(S.PDiag(diag) << StringRef(conversionPosition, 1),
+                         getLocationOfByte(conversionPosition),
+                         /*IsStringLocation*/true,
+                         Range, FixItHint::CreateRemoval(Range));
+}
+
 // Determines if the specified is a C++ class or struct containing
 // a member with the specified name and kind (e.g. a CXXMethodDecl named
 // "c_str()").