diff --git a/src/pkg/runtime/defs_nacl_amd64p32.h b/src/pkg/runtime/defs_nacl_amd64p32.h
index 8d3068bf87..45663d40af 100644
--- a/src/pkg/runtime/defs_nacl_amd64p32.h
+++ b/src/pkg/runtime/defs_nacl_amd64p32.h
@@ -79,7 +79,7 @@ struct ExcContext
 	union {
 		ExcRegs386	regs;
 		ExcRegsAmd64	regs64;
-	};
+	} regs;
 };
 
 struct ExcPortableContext
diff --git a/src/pkg/runtime/signal_nacl_amd64p32.h b/src/pkg/runtime/signal_nacl_amd64p32.h
index c58593a291..f62305cb52 100644
--- a/src/pkg/runtime/signal_nacl_amd64p32.h
+++ b/src/pkg/runtime/signal_nacl_amd64p32.h
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-#define SIG_REGS(ctxt) (((ExcContext*)(ctxt))->regs64)
+#define SIG_REGS(ctxt) (((ExcContext*)(ctxt))->regs.regs64)
 
 #define SIG_RAX(info, ctxt) (SIG_REGS(ctxt).rax)
 #define SIG_RBX(info, ctxt) (SIG_REGS(ctxt).rbx)