Index: clang/lib/Driver/ToolChains/FreeBSD.h
===================================================================
--- clang/lib/Driver/ToolChains/FreeBSD.h
+++ clang/lib/Driver/ToolChains/FreeBSD.h
@@ -69,7 +69,7 @@
       const llvm::opt::ArgList &Args) const override;
   bool isPIEDefault() const override;
   SanitizerMask getSupportedSanitizers() const override;
-  unsigned GetDefaultDwarfVersion() const override { return 2; }
+  unsigned GetDefaultDwarfVersion() const override;
   // Until dtrace (via CTF) and LLDB can deal with distributed debug info,
   // FreeBSD defaults to standalone/full debug info.
   bool GetDefaultStandaloneDebug() const override { return true; }
Index: clang/lib/Driver/ToolChains/FreeBSD.cpp
===================================================================
--- clang/lib/Driver/ToolChains/FreeBSD.cpp
+++ clang/lib/Driver/ToolChains/FreeBSD.cpp
@@ -364,6 +364,12 @@
   return ToolChain::CST_Libstdcxx;
 }
 
+unsigned FreeBSD::GetDefaultDwarfVersion() const {
+  if (getTriple().getOSMAjorVersion() < 12)
+    return 2;
+  return 4;
+}
+
 void FreeBSD::addLibStdCxxIncludePaths(
     const llvm::opt::ArgList &DriverArgs,
     llvm::opt::ArgStringList &CC1Args) const {