diff --git a/cc/config/riscv64_device.go b/cc/config/riscv64_device.go
index 35c57f9..70e9fe4 100644
--- a/cc/config/riscv64_device.go
+++ b/cc/config/riscv64_device.go
@@ -28,6 +28,7 @@
 		"-fno-emulated-tls",
 		// For -fsanitize=shadow-call-stack.
 		"-ffixed-x18",
+		"-march=rv64gc_zbb",
 	}
 
 	riscv64ArchVariantCflags = map[string][]string{}
@@ -36,6 +37,7 @@
 		"-Wl,--hash-style=gnu",
 		// For -fsanitize=shadow-call-stack.
 		"-ffixed-x18",
+		"-march=rv64gc_zbb",
 	}
 
 	riscv64Lldflags = append(riscv64Ldflags,