[Driver][OpenBSD] Enable unwind tables on all architectures

(cherry picked from commit bcbb037)

Author: mordak

clang/lib/Driver/ToolChains/OpenBSD.h

@@ -82,6 +82,10 @@ class LLVM_LIBRARY_VISIBILITY OpenBSD : public Generic_ELF {
   std::string getCompilerRT(const llvm::opt::ArgList &Args, StringRef Component,
                             FileType Type = ToolChain::FT_Static) const override;
 
+  bool IsUnwindTablesDefault(const llvm::opt::ArgList &Args) const override {
+    return true;
+  }
+
   LangOptions::StackProtectorMode
   GetDefaultStackProtectorLevel(bool KernelOrKext) const override {
     return LangOptions::SSPStrong;

clang/test/Driver/openbsd.c

@@ -121,3 +121,10 @@
 // RUN: %clang -target powerpc-unknown-openbsd -### -c %s 2>&1 \
 // RUN:   | FileCheck -check-prefix=CHECK-POWERPC-SECUREPLT %s
 // CHECK-POWERPC-SECUREPLT: "-target-feature" "+secure-plt"
+
+// Check that unwind tables are enabled
+// RUN: %clang -target arm-unknown-openbsd -### -S %s 2>&1 | \
+// RUN: FileCheck -check-prefix=UNWIND-TABLES %s
+// RUN: %clang -target mips64-unknown-openbsd -### -S %s 2>&1 | \
+// RUN: FileCheck -check-prefix=UNWIND-TABLES %s
+// UNWIND-TABLES: "-funwind-tables=2"