Add build tests for Thumb and Thumb2 with clang

Signed-off-by: Dave Rodgman <dave.rodgman@gmail.com>
diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index 87defc0..ca486ab 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -3156,6 +3156,25 @@
     not grep __aeabi_lmul library/*.o
 }
 
+component_build_arm_clang_thumb () {
+    # ~ 30s
+
+    scripts/config.py baremetal
+
+    msg "build: clang thumb 2, make"
+    make clean
+    make CC="clang" CFLAGS='-std=c99 -Werror -Os --target=arm-linux-gnueabihf -march=armv7-m -mthumb' lib
+
+    # Some Thumb 1 asm is sensitive to optimisation level, so test both -O0 and -Os
+    msg "build: clang thumb 1 -O0, make"
+    make clean
+    make CC="clang" CFLAGS='-std=c99 -Werror -O0 --target=arm-linux-gnueabihf -mcpu=arm1136j-s -mthumb' lib
+
+    msg "build: clang thumb 1 -Os, make"
+    make clean
+    make CC="clang" CFLAGS='-std=c99 -Werror -Os --target=arm-linux-gnueabihf -mcpu=arm1136j-s -mthumb' lib
+}
+
 component_build_armcc () {
     msg "build: ARM Compiler 5"
     scripts/config.py baremetal