diff --git a/common.mk b/common.mk
index b4f4d644..1993c475 100644
--- a/common.mk
+++ b/common.mk
@@ -71,7 +71,7 @@ else
 	lookup_srcs = $(shell fd -L ".*\.$(2)" $(1))
 endif
 
-SOURCE_DIRS = $(addprefix $(base_dir)/,generators sims/firesim/sim tools/barstools/iocell fpga/fpga-shells fpga/src)
+SOURCE_DIRS = $(addprefix $(base_dir)/,generators sims/firesim/sim tools/barstools fpga/fpga-shells fpga/src)
 SCALA_SOURCES = $(call lookup_srcs,$(SOURCE_DIRS),scala)
 VLOG_SOURCES = $(call lookup_srcs,$(SOURCE_DIRS),sv) $(call lookup_srcs,$(SOURCE_DIRS),v)
 # This assumes no SBT meta-build sources