Add support for -Wwrite-strings. Patch by Mike M! Fixes PR 4804.

llvm-svn: 98541

3 files changed, 5 insertions, 2 deletions

diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 64a42bc0ec4..5798f2f7100 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -474,6 +474,8 @@ static void LangOptsToArgs(const LangOptions &Opts,
     Res.push_back("-fcatch-undefined-behavior");
   if (Opts.WritableStrings)
     Res.push_back("-fwritable-strings");
+  if (Opts.ConstStrings)
+    Res.push_back("-Wwrite-strings");
   if (!Opts.LaxVectorConversions)
     Res.push_back("-fno-lax-vector-conversions");
   if (Opts.AltiVec)
@@ -1162,6 +1164,7 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args,
   Opts.PascalStrings = Args.hasArg(OPT_fpascal_strings);
   Opts.Microsoft = Args.hasArg(OPT_fms_extensions);
   Opts.WritableStrings = Args.hasArg(OPT_fwritable_strings);
+  Opts.ConstStrings = Args.hasArg(OPT_Wwrite_strings);
   if (Args.hasArg(OPT_fno_lax_vector_conversions))
     Opts.LaxVectorConversions = 0;
   if (Args.hasArg(OPT_fno_threadsafe_statics))
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index cd049a27c1b..a39ba2f7d06 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -370,7 +370,7 @@ Sema::ActOnStringLiteral(const Token *StringToks, unsigned NumStringToks) {
   if (Literal.Pascal) StrTy = Context.UnsignedCharTy;
 
   // A C++ string literal has a const-qualified element type (C++ 2.13.4p1).
-  if (getLangOptions().CPlusPlus)
+  if (getLangOptions().CPlusPlus || getLangOptions().ConstStrings )
     StrTy.addConst();
 
   // Get an array type for the string, according to C99 6.4.5.  This includes
diff --git a/clang/lib/Sema/SemaExprObjC.cpp b/clang/lib/Sema/SemaExprObjC.cpp
index c60455d8456..c98ba435c78 100644
--- a/clang/lib/Sema/SemaExprObjC.cpp
+++ b/clang/lib/Sema/SemaExprObjC.cpp
@@ -106,7 +106,7 @@ Expr *Sema::BuildObjCEncodeExpression(SourceLocation AtLoc,
     // which is an array type.
     StrTy = Context.CharTy;
     // A C++ string literal has a const-qualified element type (C++ 2.13.4p1).
-    if (getLangOptions().CPlusPlus)
+    if (getLangOptions().CPlusPlus || getLangOptions().ConstStrings)
       StrTy.addConst();
     StrTy = Context.getConstantArrayType(StrTy, llvm::APInt(32, Str.size()+1),
                                          ArrayType::Normal, 0);