Add message to test output if a test is aborted due to a timeout. Without this an aborted test could produce an empty .err file so the diff looks like as if all lines of the .out files are just missing for some unknown reason.

CC := gcc
CFLAGS := -g -O2 -Wall -Werror

prefix ?= /usr/bin

hgsh: hgsh.o
	$(CC) -o $@ $<

install: hgsh
	install -m755 hgsh $(prefix)

clean:
	rm -f *.o hgsh