diff --git a/readme.txt b/readme.txt
index a2987aa7b..96e7c8c30 100644
--- a/readme.txt
+++ b/readme.txt
@@ -74,6 +74,7 @@
 *****************************************************************************
 
 *** 20.3.5 ***
+- FIX: Fixed RT testbuild application broken (bug #1208).
 - FIX: Fixed USB not enabled on STM32F103x6 (bug #1206).
 - FIX: Fixed wrong number of CAN filters for STM32L496/9A6 (bug #1204).
 - FIX: Fixed DMA stream not disabled in STM32 QUADSPIv1 driver (bug #1203).
diff --git a/test/rt/testbuild/Makefile b/test/rt/testbuild/Makefile
index 3d5c7b102..ac45364ba 100755
--- a/test/rt/testbuild/Makefile
+++ b/test/rt/testbuild/Makefile
@@ -113,7 +113,7 @@ GCOVSRC = $(KERNSRC)
 #
 
 # List all user C define here, like -D_DEBUG=1
-UDEFS = -DSIMULATOR -DTEST_CFG_SIZE_REPORT=0
+UDEFS = -DSIMULATOR -DTEST_CFG_SIZE_REPORT=0 $(XDEFS)
 
 # Define ASM defines here
 UADEFS =
@@ -153,7 +153,7 @@ BIN  = $(CP) -O binary
 COV  = gcov
 
 # Define C warning options here
-CWARN = -Wall -Wextra -Wundef -Wstrict-prototypes
+CWARN = -Wall -Wextra -Wundef -Wstrict-prototypes -Wcast-align=strict
 
 # Define C++ warning options here
 CPPWARN = -Wall -Wextra -Wundef
diff --git a/test/rt/testbuild/Makefile_win32 b/test/rt/testbuild/Makefile_win32
index 254ab3cc3..0508a3626 100755
--- a/test/rt/testbuild/Makefile_win32
+++ b/test/rt/testbuild/Makefile_win32
@@ -113,7 +113,7 @@ GCOVSRC = $(KERNSRC)
 #
 
 # List all user C define here, like -D_DEBUG=1
-UDEFS = -DSIMULATOR -DTEST_CFG_SIZE_REPORT=0
+UDEFS = -DSIMULATOR -DTEST_CFG_SIZE_REPORT=0 $(XDEFS)
 
 # Define ASM defines here
 UADEFS =
@@ -153,7 +153,7 @@ BIN  = $(CP) -O binary
 COV  = gcov
 
 # Define C warning options here
-CWARN = -Wall -Wextra -Wundef -Wstrict-prototypes
+CWARN = -Wall -Wextra -Wundef -Wstrict-prototypes -Wcast-align=strict
 
 # Define C++ warning options here
 CPPWARN = -Wall -Wextra -Wundef
diff --git a/test/rt/testbuild/go.sh b/test/rt/testbuild/go.sh
index 0d9b2bb99..cfe3aa435 100644
--- a/test/rt/testbuild/go.sh
+++ b/test/rt/testbuild/go.sh
@@ -92,7 +92,7 @@ test cfg2 "-DCH_CFG_OPTIMIZE_SPEED=FALSE"
 test cfg3 "-DCH_CFG_TIME_QUANTUM=0"
 test cfg4 "-DCH_CFG_USE_REGISTRY=FALSE -DCH_CFG_USE_DYNAMIC=FALSE"
 test cfg5 "-DCH_CFG_USE_TM=FALSE"
-test cfg6 "-DCH_CFG_USE_SEMAPHORES=FALSE -DCH_CFG_USE_MAILBOXES=FALSE -DCH_CFG_USE_OBJ_FIFOS=FALSE"
+test cfg6 "-DCH_CFG_USE_SEMAPHORES=FALSE -DCH_CFG_USE_MAILBOXES=FALSE -DCH_CFG_USE_OBJ_FIFOS=FALSE -DCH_CFG_USE_OBJ_CACHES=FALSE -DCH_CFG_USE_JOBS=FALSE"
 test cfg7 "-DCH_CFG_USE_SEMAPHORES_PRIORITY=TRUE"
 test cfg8 "-DCH_CFG_USE_MUTEXES=FALSE -DCH_CFG_USE_CONDVARS=FALSE"
 test cfg9 "-DCH_CFG_USE_MUTEXES_RECURSIVE=TRUE"
@@ -100,12 +100,12 @@ test cfg10 "-DCH_CFG_USE_CONDVARS=FALSE"
 test cfg11 "-DCH_CFG_USE_CONDVARS_TIMEOUT=FALSE"
 test cfg12 "-DCH_CFG_USE_EVENTS=FALSE"
 test cfg13 "-DCH_CFG_USE_EVENTS_TIMEOUT=FALSE"
-test cfg14 "-DCH_CFG_USE_MESSAGES=FALSE"
+test cfg14 "-DCH_CFG_USE_MESSAGES=FALSE -DCH_CFG_USE_DELEGATES=FALSE"
 test cfg15 "-DCH_CFG_USE_MESSAGES_PRIORITY=TRUE"
-test cfg16 "-DCH_CFG_USE_MAILBOXES=FALSE -DCH_CFG_USE_OBJ_FIFOS=FALSE"
-test cfg17 "-DCH_CFG_USE_MEMCORE=FALSE -DCH_CFG_USE_MEMPOOLS=FALSE -DCH_CFG_USE_HEAP=FALSE -DCH_CFG_USE_DYNAMIC=FALSE -DCH_CFG_USE_OBJ_FIFOS=FALSE -DCH_CFG_USE_FACTORY=FALSE"
-test cfg18 "-DCH_CFG_USE_MEMPOOLS=FALSE -DCH_CFG_USE_HEAP=FALSE -DCH_CFG_USE_DYNAMIC=FALSE -DCH_CFG_USE_OBJ_FIFOS=FALSE -DCH_CFG_USE_FACTORY=FALSE"
-test cfg19 "-DCH_CFG_USE_MEMPOOLS=FALSE -DCH_CFG_USE_OBJ_FIFOS=FALSE -DCH_CFG_USE_FACTORY=FALSE"
+test cfg16 "-DCH_CFG_USE_MAILBOXES=FALSE -DCH_CFG_USE_OBJ_FIFOS=FALSE -DCH_CFG_USE_JOBS=FALSE"
+test cfg17 "-DCH_CFG_USE_MEMCORE=FALSE -DCH_CFG_USE_MEMPOOLS=FALSE -DCH_CFG_USE_HEAP=FALSE -DCH_CFG_USE_DYNAMIC=FALSE -DCH_CFG_USE_OBJ_FIFOS=FALSE -DCH_CFG_USE_JOBS=FALSE -DCH_CFG_USE_FACTORY=FALSE"
+test cfg18 "-DCH_CFG_USE_MEMPOOLS=FALSE -DCH_CFG_USE_HEAP=FALSE -DCH_CFG_USE_DYNAMIC=FALSE -DCH_CFG_USE_OBJ_FIFOS=FALSE -DCH_CFG_USE_JOBS=FALSE -DCH_CFG_USE_FACTORY=FALSE"
+test cfg19 "-DCH_CFG_USE_MEMPOOLS=FALSE -DCH_CFG_USE_OBJ_FIFOS=FALSE -DCH_CFG_USE_JOBS=FALSE -DCH_CFG_USE_FACTORY=FALSE"
 test cfg20 "-DCH_CFG_USE_HEAP=FALSE -DCH_CFG_USE_FACTORY=FALSE"
 test cfg21 "-DCH_CFG_USE_DYNAMIC=FALSE"
 test cfg22 "-DCH_DBG_STATISTICS=TRUE"