Hello dear developers of a Make,
Our team faced some race problems while building a project with Make.
Precise analysis shows that the problem was in fact, that Make doesn't care if we have different aliases for the same target.
For example:
```
.PHONY: all ../1/../main.o ../2/../main.o
all: ../1/../main.o ../2/../main.o
../1/../main.o:
ccache gcc -o $@ -c ../main.c
../2/../main.o:
ccache gcc -o $@ -c ../main.c
```
Here, we have 2 targets:
../1/../main.o
../2/../main.o
In fact, this is the same target/file (taking into account relative directories).
As a result if Make will create several threads (for each target) main.o file will be fritten concurrently (race condition).
Make doesn't operate in a wrong way.
Anyway, I think it would be great to have an additional checker in a Makefile which (at least) will notify the operator about the problem in a Makefile.
P.S. Makefile project, using which it is possible to reproduce the problem is attached to this mail.
build_race.tar