Stop the script on the first error using the set -e command

build.sh

@@ -1,4 +1,5 @@
 #!/bin/sh
+set -e
 make -C gcc clean
 make -C gcc old
 mv gcc/old_agbcc .

install.sh

@@ -1,4 +1,5 @@
 #!/bin/sh
+set -e
 if [ "$1" != "" ]; then
     mkdir -p $1/tools/agbcc
     mkdir -p $1/tools/agbcc/bin