diff --git a/examples/posix_spawn/Makefile b/examples/posix_spawn/Makefile
index 2e5aa7b58..312d04378 100644
--- a/examples/posix_spawn/Makefile
+++ b/examples/posix_spawn/Makefile
@@ -24,6 +24,8 @@ include $(APPDIR)/Make.defs
 
 CSRCS = romfs.c
 CSRCS += symtab.c
+filesystem$(DELIM)symtab.c_CFLAGS = -fno-builtin
+filesystem$(DELIM)symtab.c_CELFFLAGS = -fno-builtin
 MAINSRC = spawn_main.c
 
 PROGNAME = posix_spawn