diff --git a/Makefrag b/Makefrag
index 33cd334e..129cd44f 100644
--- a/Makefrag
+++ b/Makefrag
@@ -8,9 +8,11 @@ PROJECT := rocketchip
 CXX ?= g++
 CXXFLAGS := -O1
 
-CHISEL_VERSION=2
+CHISEL_VERSION ?= 2
+CHISEL_SUBMODULE ?= chisel$(CHISEL_VERSION)
+export CHISEL_SUBMODULE
 
-SBT := CHISEL_SUBMODULE="chisel$(CHISEL_VERSION)" java -Xmx2048M -Xss8M -XX:MaxPermSize=256M -jar sbt-launch.jar
+SBT ?= java -Xmx2G -Xss8M -XX:MaxPermSize=256M -jar sbt-launch.jar
 SHELL := /bin/bash
 
 ifeq ($(CHISEL_VERSION),2)
diff --git a/chisel3 b/chisel3
index 84e9b709..19046381 160000
--- a/chisel3
+++ b/chisel3
@@ -1 +1 @@
-Subproject commit 84e9b70989d62e2e1d453d1c418a31c54db6fa1a
+Subproject commit 19046381ae319915c4e8fff7b108e6b5dd100509
diff --git a/firrtl b/firrtl
index 16839288..484262d6 160000
--- a/firrtl
+++ b/firrtl
@@ -1 +1 @@
-Subproject commit 168392889d42506fae5a1aa637ebe1e61d799e62
+Subproject commit 484262d6ce6979276853cbe202fc038b4700ce2d
diff --git a/torture b/torture
index b54b3d0d..007b5b1e 160000
--- a/torture
+++ b/torture
@@ -1 +1 @@
-Subproject commit b54b3d0d80cd620ddcce1680201c6f366051d150
+Subproject commit 007b5b1eccc0e36b70d87b7896049909abf32470