On 3/31/20 5:37 AM, Daniel P. Berrangé wrote:
Running configure directly from the source directory is a build
configuration that will go away in future. It is also not currently
covered by any automated testing. Display a deprecation warning if
the user attempts to use an in-srcdir build setup, so that they are
aware that they're building QEMU in an undesirable manner.
Signed-off-by: Daniel P. Berrangé <address@hidden>
---
configure | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
It sounds like you already have a v2 coming up to address Phillipe's
comments, but I'd be happy to see this concept make it into v5.0.
diff --git a/configure b/configure
index e225a1e3ff..1ab7492ab5 100755
--- a/configure
+++ b/configure
@@ -3,6 +3,19 @@
# qemu configure script (c) 2003 Fabrice Bellard
#
+BUILDDIR=$(pwd)
Why fork out to 'pwd', when we can rely on $PWD for the same answer? Note
that both $(pwd) and $PWD $BUILDDIR always give an absolute (but no
necessarily canonical) path, which means...
+SRCDIR=$(dirname "$0")
+
+ABS_BUILDDIR=$(realpath $BUILDDIR)
...calling this ABS_BUILDDIR is a misnomer (it was already absolute). What it
is really doing is chasing through symlinks to result in a canonical name,
particularly since unless you have absolute names, using only string
comparison to see if two filenames are equivalent will have false negatives
(/tmp vs. /tmp/., for example).
+ABS_SRCDIR=$(realpath $SRCDIR)
Not robust if there are spaces in the directory names. Safer would be
ABS_BUILDDIR=$(realpath -- "$BUILDDIR")
and similarly for ABS_SRCDIR.
+
+in_srcdir=no
+if [ "$ABS_SRCDIR" == "$ABS_BUILDDIR" ]
Bashism. You MUST spell this '=', not '==', since configure is run under
/bin/sh which might be dash which does not understand ==.
+then
+ in_srcdir=yes
+fi
+
+
# Unset some variables known to interfere with behavior of common tools,
# just as autoconf does.
CLICOLOR_FORCE= GREP_OPTIONS=
@@ -6799,6 +6812,23 @@ if test "$supported_os" = "no"; then
echo "us upstream at address@hidden."
fi
+if test "$in_srcdir" = "yes"; then
+ echo
+ echo "WARNING: SUPPORT FOR IN SOURCE DIR BUILDS IS DEPRECATED"
+ echo
+ echo "Support for running the 'configure' script directly from the"
+ echo "source directory is deprecated and will go away in a future"
+ echo "release. In source dir builds are not covered by automated"
+ echo "testing and are liable to break without warning. Users are"
+ echo "strongly recommended to switch to a separate build directory:"
+ echo
+ echo " $ mkdir build"
+ echo " $ cd build"
+ echo " $ ../configure"
+ echo " $ make"
+ echo
+fi
You know, it WOULD be possible to further enhance this to actually create
'build' as well as a shim GNUmakefile that would auto-forward on to building
directly in build, so that you maintain the illusion of an in-place build
(other than all the build artifacts now living in a different location), and
muscle memory for in-tree 'make' still works; I've posted elsewhere and will
repeat here the contents of my GNUmakefile:
# Hack for redirecting while reminding myself to use distinct builddir
ifeq ($(MAKECMDGOALS),)
recurse: all
endif
%: force
@echo 'changing directory to build...'
@sleep 2