No rule to make target `/Makefile', needed by `Makefile'

I'm trying to 'make' using a pretty simple makefile. My makefile is named 'Makefile' so I'm simply using the command 'make'.

I get this strange error:

make: *** No rule to make target `/Makefile', needed by `Makefile'. Stop.

If, however, I use make -f "full-path-to-makefile" it actually does run (with odd consequences...). I should say that I'm running all this from the directory where the Makefile lies, of course.

I'm working on Mac OSX, using tcsh.

Edit:

I'm working in the LLVM framework, trying to com开发者_如何学Gopile a pass function and this is the associated makefile:

LEVEL = ../../../
LIBRARYNAME = FunctionName
LOADABLE_MODULE = 1
include $(LEVEL)/Makefile.common

Any ideas will be appreciated :)

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I had the same problem trying to write a new pass for LLVM i followed these instructions trying to make a HelloB (as Hello already exsited) http://llvm.org/docs/WritingAnLLVMPass.html#quickstart

What i has to do was do a ./configure again then make from the base directory.

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I'll go out on a limb: you have an extra slash. Try omitting the final slash in $(LEVEL).

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I found the answer, sort of:

The problem was with the installation process of LLVM. It seems that if you do the installation in one order instead of another it can lead to this error. It doesn't make any sense to me, but after I installed it properly everything compiles great (same code, same Makefile, same make program).

I don't really know why this happened, but I know how to fix it :)

What you want to do is ./configure again then make from the base directory (contrary to what is stated in the instructions on the web-site). That worked for me.

BTW - I got the same results running on Ubuntu (with the same fix).

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Just to add some information here (since this is the first hit that comes up on Google when looking for the error) - I had the same problem which suddenly popped up on a (previously working) LLVM setup on OSX, and traced it back to the behavior of the realpath command in make.

Specifically, what was happening was that I had a directory called "LLVM/llvm-2.9-build", but for some reason the attempt to resolve PROJECT_OBJ_ROOT at the top of Makefile.config would decide that this directory was in fact called "llvm/llvm-2.9-build". Since OSX is case-insensitive by default, this doesn't cause an immediate problem, except that subsequently LLVM_SRC_ROOT would be set to "LLVM/llvm-2.9-build". This then meant that the creation of PROJ_SRC_DIR using patsubst to replace the object directory would result in a non-existent path (as the unmatched case means that no pattern replace occurs), which in turn would get resolved to / by realpath.

With PROJ_SRC_DIR set to /, this results in the makefile copy rule in Makefile.rules deciding that the source makefile is at $(PROJ_SRC_DIR)/Makefile (ie /Makefile), and the error message described.

It seems that it is only the built-in implementation of realpath in Make (GNU Make 3.81 in my case) that has this behaviour, as forcibly using the macro version of realpath from the top of Makefile.config fixes the problem. However, this isn't a good long-term fix, as you'd have to manually patch every one of the LLVM makefiles.

In the end, I couldn't see where realpath would be getting the lower-case "llvm" from, but figured it was probably an artifact somehow of some caching of the name from a point in time when I'd referenced the directory using its lower-case name. Hence I tried going to that directory and mv-ing it to a completely different name, and then back to "LLVM" before going in and building again, and that seems to have solved the problem.

I hope that's of some use to anyone else who comes across this particular weirdness!

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It's not a complete answer, but what you are seeing is gmake not finding the Makefile it is told to include, and thus it is trying to remake it and failing because it can't find a recipe for it either.

However, the Makefile snippet you posted does not produce the error message you are seeing, so I think the problem is inside the Makefile.common file. Look for include statements which reference a $(some variable expansion)/Makefile and work backwards from there. You can also try to run gmake with the -d option and follow the processing based on the output.

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Since your include line reads:

include $(LEVEL)/Makefile.common

it is puzzling that you are not getting an error about /Makefile.common. If you were, then I'd suggest that maybe you have a trailing blank after the definition of LEVEL.

Could there be a line in Makefile.common that itself includes $(SOMEMACRO)/Makefile and you have not set the value of SOMEMACRO?

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here's my fixes for this issue: (https://github.com/rust-lang/rust/issues/24887#issuecomment-99391849)

update src/llvm/Makefile.config.in before running ./configure

or update x86_64-apple-darwin/llvm/Makefile.config before make

line 59:

PROJ_SRC_DIR    := $(LLVM_SRC_ROOT)$(patsubst $(PROJ_OBJ_ROOT)%,%,$(PROJ_OBJ_DIR))

update to

PROJ_SRC_DIR    := $(patsubst $(PROJ_OBJ_ROOT)%,$(LLVM_SRC_ROOT)%,$(PROJ_OBJ_DIR))

line 86:

PROJ_SRC_DIR := $(call realpath, $(PROJ_SRC_ROOT)/$(patsubst $(PROJ_OBJ_ROOT)%,%,$(PROJ_OBJ_DIR)))

update to

PROJ_SRC_DIR := $(call realpath, $(patsubst $(PROJ_OBJ_ROOT)%,$(PROJ_SRC_ROOT)%,$(PROJ_OBJ_DIR)))