From d1bd2423a90a144576cd140dc84b1fe8c7c8fda0 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Fri, 19 Oct 2012 14:54:23 +0100 Subject: [PATCH] Makefile: Forbid out-of-tree build from a source tree that has been built in If we try to do an out-of-tree build but the source tree we're building from has been used in the past for an in-tree build then things will go confusingly wrong. Specifically, some parts of the build process will pull in generated files from the old in-tree build (because SRC_PATH is on the vpath). Diagnose this situation so we can produce a useful error message and tell the user how to fix it (run distclean in the source tree). Signed-off-by: Peter Maydell Signed-off-by: Blue Swirl --- Makefile | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/Makefile b/Makefile index 17e2d58ce5..b522b10195 100644 --- a/Makefile +++ b/Makefile @@ -8,6 +8,17 @@ ifneq ($(wildcard config-host.mak),) # Put the all: rule here so that config-host.mak can contain dependencies. all: include config-host.mak + +# Check that we're not trying to do an out-of-tree build from +# a tree that's been used for an in-tree build. +ifneq ($(realpath $(SRC_PATH)),$(realpath .)) +ifneq ($(wildcard $(SRC_PATH)/config-host.mak),) +$(error This is an out of tree build but your source tree ($(SRC_PATH)) \ +seems to have been used for an in-tree build. You can fix this by running \ +"make distclean && rm -rf *-linux-user *-softmmu" in your source tree) +endif +endif + include $(SRC_PATH)/rules.mak config-host.mak: $(SRC_PATH)/configure @echo $@ is out-of-date, running configure