diff --git a/clang/lib/Driver/ToolChains/WebAssembly.h b/clang/lib/Driver/ToolChains/WebAssembly.h
--- a/clang/lib/Driver/ToolChains/WebAssembly.h
+++ b/clang/lib/Driver/ToolChains/WebAssembly.h
@@ -51,6 +51,7 @@
   bool hasBlocksRuntime() const override;
   bool SupportsProfiling() const override;
   bool HasNativeLLVMSupport() const override;
+  unsigned GetDefaultDwarfVersion() const override { return 4; }
   void
   addClangTargetOptions(const llvm::opt::ArgList &DriverArgs,
                         llvm::opt::ArgStringList &CC1Args,
diff --git a/clang/test/Driver/debug-options.c b/clang/test/Driver/debug-options.c
--- a/clang/test/Driver/debug-options.c
+++ b/clang/test/Driver/debug-options.c
@@ -132,6 +132,15 @@
 // RUN: %clang -### -c -g %s -target powerpc64-ibm-aix-xcoff -gcolumn-info \
 // RUN:             2>&1 | FileCheck -check-prefix=CI %s
 
+// WebAssembly.
+// WebAssembly should default to DWARF4.
+// RUN: %clang -### -c -g %s -target wasm32 -gdwarf-4 2>&1 \
+// RUN:             | FileCheck -check-prefix=G_DWARF4 %s
+// RUN: %clang -### -c -g %s -target wasm64 -gdwarf-4 2>&1 \
+// RUN:             | FileCheck -check-prefix=G_DWARF4 %s
+
+
+
 // RUN: %clang -### -c -gdwarf-2 %s 2>&1 \
 // RUN:             | FileCheck -check-prefix=G_ONLY_DWARF2 %s
 //