Why does my makefile call rm on dependencies after building? - makefile

Question

When I run make -j tests, it makes the tests just fine but removes the dependencies afterwards. Why is it doing this and how can I solve it? I apologize for the complicated makefile. The relevant portions of the makefile are the Test sections.
Makefile:
# Build tools
CC = clang++ -g --std=gnu++11 -O3
LEX = flex
YACC = bison -d
# Includes
CC_HEADERS = `llvm-config-3.5 --cppflags`
CC_LIBRARIES = -lboost_program_options `llvm-config-3.5 --libs all --ldflags` -ltinfo -lpthread -lffi -ldl -lm -lz
# Created files
GENERATED_SOURCES = parser.cpp tokens.cpp
GENERATED_FILES = $(GENERATED_SOURCES)
EXEC = brainfuck.out
# Test cases
TESTS = $(wildcard ./tests/*.bf)
TESTS_IN = $(TESTS:.bf=.in)
TESTS_BUILD = $(TESTS:.bf=.build)
TESTS_EXPECTED = $(TESTS:.bf=.expected)
TESTS_ACTUAL = $(TESTS:.bf=.actual)
TESTS_DIFF = $(TESTS:.bf=.diff)
GENERATED_FILES += $(TESTS_BUILD) $(TESTS_EXPECTED) $(TESTS_ACTUAL) $(TESTS_DIFF)
# Generic config
SOURCES = $(filter-out $(GENERATED_SOURCES), $(wildcard *.cpp))
SOURCES += $(GENERATED_SOURCES)
OBJECTS = $(SOURCES:.cpp=.o)
# Main targets
target: $(EXEC)
all: target tests
# Generated source targets
tokens.cpp: tokens.l parser.hpp
$(LEX) -o $# $<
parser.hpp: parser.cpp
parser.cpp: parser.y
$(YACC) -o $# $<
# Test targets
tests: $(TESTS_DIFF)
#echo ""
#echo "#####################"
#echo "# Begin test output #"
#echo "#####################"
#$(foreach f,$^, echo "Test:" $(f:.diff=.bf); cat $(f); echo "";)
#echo "#####################"
#echo "# End test output #"
#echo "#####################"
#echo ""
tests/%.build: tests/%.bf $(EXEC)
./brainfuck.out $< -p | llc-3.5 - -o - | gcc -O0 -x assembler - -o $#
tests/%.expected: tests/%.bf tests/%.in
-bf -c65535 $< < $(word 2,$^) > $#
tests/%.actual: tests/%.build tests/%.in
-$< < $(word 2,$^) > $#
tests/%.diff: tests/%.expected tests/%.actual
-diff $< $(word 2,$^) > $#
# Generic targets
clean:
rm -rf $(EXEC) $(OBJECTS) $(GENERATED_FILES) $(GENERATED_SOURCES:.cpp=.hpp)
$(EXEC): $(OBJECTS)
$(CC) -o $# ${OBJECTS} $(CC_LIBRARIES)
%.o: %.cpp parser.hpp
$(CC) $(CC_HEADERS) -c $< -o $#
Make output:
bf -c65535 tests/awib-0.4.bf < tests/awib-0.4.in > tests/awib-0.4.expected
./brainfuck.out tests/awib-0.4.bf -p | llc-3.5 - -o - | gcc -O0 -x assembler - -o tests/awib-0.4.build
bf -c65535 tests/dbfi.bf < tests/dbfi.in > tests/dbfi.expected
./brainfuck.out tests/dbfi.bf -p | llc-3.5 - -o - | gcc -O0 -x assembler - -o tests/dbfi.build
bf -c65535 tests/factor.bf < tests/factor.in > tests/factor.expected
./brainfuck.out tests/factor.bf -p | llc-3.5 - -o - | gcc -O0 -x assembler - -o tests/factor.build
bf -c65535 tests/hanoi.bf < tests/hanoi.in > tests/hanoi.expected
./brainfuck.out tests/hanoi.bf -p | llc-3.5 - -o - | gcc -O0 -x assembler - -o tests/hanoi.build
bf -c65535 tests/long.bf < tests/long.in > tests/long.expected
./brainfuck.out tests/long.bf -p | llc-3.5 - -o - | gcc -O0 -x assembler - -o tests/long.build
bf -c65535 tests/mandelbrot.bf < tests/mandelbrot.in > tests/mandelbrot.expected
./brainfuck.out tests/mandelbrot.bf -p | llc-3.5 - -o - | gcc -O0 -x assembler - -o tests/mandelbrot.build
bf -c65535 tests/prime.bf < tests/prime.in > tests/prime.expected
./brainfuck.out tests/prime.bf -p | llc-3.5 - -o - | gcc -O0 -x assembler - -o tests/prime.build
tests/dbfi.build < tests/dbfi.in > tests/dbfi.actual
tests/long.build < tests/long.in > tests/long.actual
tests/factor.build < tests/factor.in > tests/factor.actual
tests/prime.build < tests/prime.in > tests/prime.actual
tests/mandelbrot.build < tests/mandelbrot.in > tests/mandelbrot.actual
tests/hanoi.build < tests/hanoi.in > tests/hanoi.actual
tests/awib-0.4.build < tests/awib-0.4.in > tests/awib-0.4.actual
diff tests/factor.expected tests/factor.actual > tests/factor.diff
diff tests/awib-0.4.expected tests/awib-0.4.actual > tests/awib-0.4.diff
diff tests/mandelbrot.expected tests/mandelbrot.actual > tests/mandelbrot.diff
diff tests/hanoi.expected tests/hanoi.actual > tests/hanoi.diff
diff tests/long.expected tests/long.actual > tests/long.diff
diff tests/prime.expected tests/prime.actual > tests/prime.diff
diff tests/dbfi.expected tests/dbfi.actual > tests/dbfi.diff
#####################
# Begin test output #
#####################
Test: tests/awib-0.4.bf
Test: tests/dbfi.bf
Test: tests/factor.bf
Test: tests/hanoi.bf
Test: tests/long.bf
Test: tests/mandelbrot.bf
Test: tests/prime.bf
#####################
# End test output #
#####################
rm tests/mandelbrot.actual tests/hanoi.build tests/long.actual tests/mandelbrot.build tests/factor.actual tests/awib-0.4.actual tests/long.build tests/prime.actual tests/hanoi.expected tests/factor.build tests/awib-0.4.build tests/dbfi.expected tests/prime.build tests/mandelbrot.expected tests/dbfi.actual tests/long.expected tests/dbfi.build tests/hanoi.actual tests/factor.expected tests/prime.expected tests/awib-0.4.expected
Notice the last line rm .... Where is this coming from?

Answer 1

The solution is to put .SECONDARY: at the top of the makefile. More info here: http://www.thinkplexx.com/learn/howto/build-chain/make-based/prevent-gnu-make-from-always-removing-files-it-says-things-like-rm-or-removing-intermediate-files
Excerpt:
GNU make does track some files, which are created during the build,
and it will remove such files after the build. The files are called
"intermediate files". They are supposed to be created by make’s "chain
of Implicit Rules". Because they were created to facilitate something
else, make considers them useless after the build and removes them.
...
.SECONDARY with no prerequisites causes all targets to be treated as
secondary (i.e., no target is removed because it is considered
intermediate