Index: clang/lib/Driver/ToolChains/CommonArgs.cpp
--- clang/lib/Driver/ToolChains/CommonArgs.cpp.orig
+++ clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -3098,7 +3098,11 @@ bool tools::shouldRecordCommandLine(const ToolChain &T
 
 void tools::renderCommonIntegerOverflowOptions(const ArgList &Args,
                                                ArgStringList &CmdArgs) {
+#ifdef __OpenBSD__
+  bool use_fwrapv = true;
+#else
   bool use_fwrapv = false;
+#endif
   bool use_fwrapv_pointer = false;
   for (const Arg *A : Args.filtered(
            options::OPT_fstrict_overflow, options::OPT_fno_strict_overflow,
