diff --git a/spike_main/spike_main.mk.in b/spike_main/spike_main.mk.in
index 25a7a6c6..c842c4ed 100644
--- a/spike_main/spike_main.mk.in
+++ b/spike_main/spike_main.mk.in
@@ -14,3 +14,7 @@ spike_main_install_prog_srcs = \
 spike_main_srcs = \
 
 spike_main_CFLAGS = -fPIC
+
+# This hack adds all symbols from extension.o to spike's dynamic symbol
+# table, which is required for dynamically loaded --extension libraries
+spike_main_LDFLAGS = extension.o