driver: Allow -fdebug-compilation-dir=foo in joined form.

All 130+ f_Group flags that take an argument allow it after a '=',
except for fdebug-complation-dir. Add a Joined<> alias so that
it behaves consistently with all the other f_Group flags.
(Keep the old Separate flag for backwards compat.)

1 files changed, 6 insertions, 0 deletions

diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 8fdf1f23e28..4ef40e974cd 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -2397,6 +2397,12 @@ static void CollectArgsForIntegratedAssembler(Compilation &C,
       } else if (Value == "-fdebug-compilation-dir") {
         CmdArgs.push_back("-fdebug-compilation-dir");
         TakeNextArg = true;
+      } else if (Value.consume_front("-fdebug-compilation-dir=")) {
+        // The flag is a -Wa / -Xassembler argument and Options doesn't
+        // parse the argument, so this isn't automatically aliased to
+        // -fdebug-compilation-dir (without '=') here.
+        CmdArgs.push_back("-fdebug-compilation-dir");
+        CmdArgs.push_back(Value.data());
       } else {
         D.Diag(diag::err_drv_unsupported_option_argument)
             << A->getOption().getName() << Value;