Driver: hoist the `wchar_t` handling to the driver

Move the logic for determining the `wchar_t` type information into the
driver.  Rather than passing the single bit of information of
`-fshort-wchar` indicate to the frontend the desired type of `wchar_t`
through a new `-cc1` option of `-fwchar-type` and indicate the
signedness through `-f{,no-}signed-wchar`.  This replicates the current
logic which was spread throughout Basic into the
`RenderCharacterOptions`.

Most of the changes to the tests are to ensure that the frontend uses
the correct type.  Add a new test set under `test/Driver/wchar_t.c` to
ensure that we calculate the proper types for the various cases.

llvm-svn: 315126

1 files changed, 10 insertions, 1 deletions

diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 37ba39dfd07..7114e654dab 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -2154,7 +2154,16 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
   Opts.ImplicitModules = !Args.hasArg(OPT_fno_implicit_modules);
   Opts.CharIsSigned = Opts.OpenCL || !Args.hasArg(OPT_fno_signed_char);
   Opts.WChar = Opts.CPlusPlus && !Args.hasArg(OPT_fno_wchar);
-  Opts.ShortWChar = Args.hasFlag(OPT_fshort_wchar, OPT_fno_short_wchar, false);
+  if (const Arg *A = Args.getLastArg(OPT_fwchar_type_EQ)) {
+    Opts.WCharSize = llvm::StringSwitch<unsigned>(A->getValue())
+                         .Case("char", 1)
+                         .Case("short", 2)
+                         .Case("int", 4)
+                         .Default(0);
+    if (Opts.WCharSize == 0)
+      Diags.Report(diag::err_fe_invalid_wchar_type) << A->getValue();
+  }
+  Opts.WCharIsSigned = Args.hasFlag(OPT_fsigned_wchar, OPT_fno_signed_wchar, true);
   Opts.ShortEnums = Args.hasArg(OPT_fshort_enums);
   Opts.Freestanding = Args.hasArg(OPT_ffreestanding);
   Opts.NoBuiltin = Args.hasArg(OPT_fno_builtin) || Opts.Freestanding;