1 files changed, 18 insertions, 7 deletions
diff --git a/llvm/lib/TextAPI/MachO/TextStubCommon.cpp b/llvm/lib/TextAPI/MachO/TextStubCommon.cpp
index cfd9ac8d0cf..183c5d5a93b 100644
--- a/llvm/lib/TextAPI/MachO/TextStubCommon.cpp
+++ b/llvm/lib/TextAPI/MachO/TextStubCommon.cpp
@@ -172,14 +172,25 @@ void ScalarTraits<SwiftVersion>::output(const SwiftVersion &Value, void *,
     break;
   }
 }
-StringRef ScalarTraits<SwiftVersion>::input(StringRef Scalar, void *,
+StringRef ScalarTraits<SwiftVersion>::input(StringRef Scalar, void *IO,
                                             SwiftVersion &Value) {
-  Value = StringSwitch<SwiftVersion>(Scalar)
-              .Case("1.0", 1)
-              .Case("1.1", 2)
-              .Case("2.0", 3)
-              .Case("3.0", 4)
-              .Default(0);
+  const auto *Ctx = reinterpret_cast<TextAPIContext *>(IO);
+  assert((!Ctx || Ctx->FileKind != FileType::Invalid) &&
+         "File type is not set in context");
+
+  if (Ctx->FileKind == FileType::TBD_V4) {
+    if (Scalar.getAsInteger(10, Value))
+      return "invalid Swift ABI version.";
+    return {};
+  } else {
+    Value = StringSwitch<SwiftVersion>(Scalar)
+                .Case("1.0", 1)
+                .Case("1.1", 2)
+                .Case("2.0", 3)
+                .Case("3.0", 4)
+                .Default(0);
+  }
+
   if (Value != SwiftVersion(0))
     return {};