make编译源文件时输出信息的问题

例子如下：
make -C ./ -f /work/own/digital/Makefile.build
make[1]: Entering directory '/work/own/digital'
make -C display -f /work/own/digital/Makefile.build
make[2]: Entering directory '/work/own/digital/display'
arm-linux-gcc -Wall -O2 -g -Werror -I /work/own/digital/include  -Wp,-MD,.disp_manager.o.d -c -o disp_manager.o disp_manager.c
arm-linux-gcc -Wall -O2 -g -Werror -I /work/own/digital/include  -Wp,-MD,.fb.o.d -c -o fb.o fb.c
arm-linux-ld -r -o built-in.o disp_manager.o fb.o
make[2]: Leaving directory '/work/own/digital/display'
make -C encoding -f /work/own/digital/Makefile.build
make[2]: Entering directory '/work/own/digital/encoding'
这种数据是由什么输出的呢 
make[1]: Entering directory '/work/own/digital'