I am seeing a line of makefile as follows:
$(LAST_TARGET_DIR)/%: LFLAGS += -lpthread -lrt -Wl,-uevaluate
In my understanding, $(LAST_TARGET_DIR)/% is a target matching, and after the target should come its dependencies. Why are linking flags changed here?
This is a feature of GNU make that allows using a different value of a variable for one specific target or pattern.
For example,
LFLAGS = -lm
$(LAST_TARGET_DIR)/%: LFLAGS += -lpthread
%.exe: %.o common.o
$(CC) -o $@ common.o $(@:%.exe=%.o) $(LFLAGS)
causes every .exe file to be linked with -lm, except that those in the directory $(LAST_TARGET_DIR) will be linked with -lm -lpthreads.
