| Message ID | 20120330152436.GA31016@aepfle.de |
|---|---|
| State | New |
| Headers | show |
Hi Olaf, Am 30.03.2012 17:24, schrieb Olaf Hering: > > configure will generate incorrect CFLAGS which will lead to compile > errors due to unknown gcc options, IFF CFLAGS was already in the > environment during configure invocation. > > Add a space before the -march=i486 gcc option. > > This patch is against the qemu-xen tree, but it should apply also to > qemu.git since it has the same issue. Please apply to both trees. > > Signed-off-by: Olaf Hering <olaf@aepfle.de> The patch applies fine to upstream QEMU (we should strip leading qemu/ from the commit message though). This is the only usage of += outside Makefile fragments, so I wonder if its use may have been by accident. Is it safe in a POSIX context? Or should we better use CFLAGS="$CFLAGS -march=486"? For QEMU_CFLAGS we use the pattern QEMU_CFLAGS="-options $QEMU_CFLAGS" to allow overriding options. Andreas > > --- > configure | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > Index: qemu-xen-dir-remote/configure > =================================================================== > --- qemu-xen-dir-remote.orig/configure > +++ qemu-xen-dir-remote/configure > @@ -2637,7 +2637,7 @@ int main(int argc, char **argv) > } > EOF > if ! compile_prog "" "" ; then > - CFLAGS+="-march=i486" > + CFLAGS+=" -march=i486" > fi > fi >
On Sat, Mar 31, Andreas Färber wrote: > This is the only usage of += outside Makefile fragments, so I wonder if > its use may have been by accident. Is it safe in a POSIX context? > Or should we better use CFLAGS="$CFLAGS -march=486"? Now that I look at the shebang, configure is a sh script and += is most likely a bash feature. So your suggestion for the assignment is correct. Olaf
On 31 March 2012 16:41, Andreas Färber <afaerber@suse.de> wrote: > This is the only usage of += outside Makefile fragments, so I wonder if > its use may have been by accident. Is it safe in a POSIX context? > Or should we better use CFLAGS="$CFLAGS -march=486"? > For QEMU_CFLAGS we use the pattern QEMU_CFLAGS="-options $QEMU_CFLAGS" > to allow overriding options. For that matter, should this be setting QEMU_CFLAGS instead of CFLAGS? I have to say I'm not entirely sure what the difference is... -- PMM
On Sat, Mar 31, Peter Maydell wrote: > On 31 March 2012 16:41, Andreas Färber <afaerber@suse.de> wrote: > > This is the only usage of += outside Makefile fragments, so I wonder if > > its use may have been by accident. Is it safe in a POSIX context? > > Or should we better use CFLAGS="$CFLAGS -march=486"? > > For QEMU_CFLAGS we use the pattern QEMU_CFLAGS="-options $QEMU_CFLAGS" > > to allow overriding options. > > For that matter, should this be setting QEMU_CFLAGS instead of > CFLAGS? I have to say I'm not entirely sure what the difference > is... I havent looked into qemu build internals, but there is most likely a concept of HOST_TOOLS_CFLAGS and TARGET_CFLAGS in qemus Makefiles. Olaf
Am 31.03.2012 18:46, schrieb Olaf Hering: > On Sat, Mar 31, Andreas Färber wrote: > >> This is the only usage of += outside Makefile fragments, so I wonder if >> its use may have been by accident. Is it safe in a POSIX context? >> Or should we better use CFLAGS="$CFLAGS -march=486"? > > Now that I look at the shebang, configure is a sh script and += is most > likely a bash feature. So your suggestion for the assignment is correct. ...apart from the missing i in i486, obviously. ;) Andreas
Index: qemu-xen-dir-remote/configure =================================================================== --- qemu-xen-dir-remote.orig/configure +++ qemu-xen-dir-remote/configure @@ -2637,7 +2637,7 @@ int main(int argc, char **argv) } EOF if ! compile_prog "" "" ; then - CFLAGS+="-march=i486" + CFLAGS+=" -march=i486" fi fi
configure will generate incorrect CFLAGS which will lead to compile errors due to unknown gcc options, IFF CFLAGS was already in the environment during configure invocation. Add a space before the -march=i486 gcc option. This patch is against the qemu-xen tree, but it should apply also to qemu.git since it has the same issue. Please apply to both trees. Signed-off-by: Olaf Hering <olaf@aepfle.de> --- configure | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)