Question

I have six source files and I would like to link them using the .elf format. I have written a makefile that converts all the source code files to .obj files.

When I attempt to link these object files using the syntax I gave in the makefile, the following errors appear:

gcc -c rt_look.c
Linking ARM test_rom.elf
make[1]: o: Command not found
make[1]: [test_rom.elf] Error 127 (ignored)
make[1]: Leaving directory `/c/Imperas/Demo/main/isolated_model_ert_rtw

I am also pasting the makefile rules:

all:$(OBJ) test_rom.elf 

ert_main.o:              ert_main.c isolated_model.h rtwtypes.h
             gcc -c ert_main.c
isolated_model.o:        isolated_model.c isolated_model.h isolated_model_private.h
             gcc -c isolated_model.c
isolated_model_date.o:   isolated_model_data.c isolated_model.h isolated_model_data.h
             gcc -c isolated_model_data.c
rt_look2d_normal.o:      rt_look2d_normal.c rtlibsrc.h
             gcc -c rt_look2d_normal.c
rt_nonfinite.o:          rt_nonfinite.c rt_nonfinite.h
             gcc -c rt_nonfinite.c
rt_look.o:           rt_look.c rtlibsrc.h
             gcc -c rt_look.c
syscalls.o:          syscalls.c
             gcc -c syscalls.c
test_rom.elf:        $(OBJ) 
                     $(V) echo "Linking $(CROSS) $@"
                     $(V) $(IMPERAS_LINK) -o $@ $^ $(IMPERAS_LDFLAGS) -lm

clean::
-rm -f test_rom.elf
-rm -f *.$(OBJ).o

endif

Answer 1

The V and IMPERAS_LINK variables are not set, or set to an empty value, so when building test_rom.elf, make runs the command

 -o $@ $^ $(IMPERAS_LDFLAGS) -lm

which attempts to run the o command. Since the first character in the command is -, make ignores the error.

Try replacing "Linking $(CROSS)" with "Linking $(CROSS) with $(IMPERAS_LINK)" to see if this is the case.