1 files changed, 13 insertions, 0 deletions
diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
index 21dc180..e612afd 100644
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -327,6 +327,19 @@ InputArgList Driver::ParseArgStrings(ArrayRef<const char *> ArgStrings,
                      DiagnosticsEngine::Warning;
   }
 
+  for (const Arg *A : Args.filtered(options::OPT_o)) {
+    if (ArgStrings[A->getIndex()] == A->getSpelling())
+      continue;
+
+    // Warn on joined arguments that are similar to a long argument.
+    std::string ArgString = ArgStrings[A->getIndex()];
+    std::string Nearest;
+    if (getOpts().findNearest("-" + ArgString, Nearest, IncludedFlagsBitmask,
+                              ExcludedFlagsBitmask) == 0)
+      Diags.Report(diag::warn_drv_potentially_misspelled_joined_argument)
+          << A->getAsString(Args) << Nearest;
+  }
+
   return Args;
 }