Re: [Qemu-devel] [PATCH 39/67] target: replace command line flags with preprocessor

[Michael S. Tsirkin]

On Thu, May 03, 2018 at 03:11:26PM -0500, Eric Blake wrote:
> On 05/03/2018 02:51 PM, Michael S. Tsirkin wrote:
> > Each target is currently built with a different set of include
> > directories, this is what makes it possible to pull in a separate copy
> > of header files depending on the target.
> > 
> > Replace with per-target ifdefs which are easier to understand.
> > 
> > Signed-off-by: Michael S. Tsirkin <address@hidden>
> > ---
> >   include/target-dir.h | 63 
> > ++++++++++++++++++++++++++++++++++++++++++++++++++++
> >   1 file changed, 63 insertions(+)
> >   create mode 100644 include/target-dir.h
> 
> Ah, now we get to the file mentioned in a couple of previous patches.

Thanks, will reorder.

> > +#ifndef QEMU_TARGET_DIR_H
> > +#define QEMU_TARGET_DIR_H
> > +
> > +#if defined(TARGET_ALPHA)
> > +#define TARGET_DIR_PREFIX ../target/alpha
> > +#elif defined(TARGET_ARM)
> > +#define TARGET_DIR_PREFIX ../target/arm
> 
> > +#elif defined(TARGET_XTENSA)
> > +#define TARGET_DIR_PREFIX ../target/xtensa
> > +#else
> > +#error "Target-specific directory include missing"
> > +#endif
> > +
> > +#define TARGET_DIR_HASH(file) #file
> > +#define TARGET_DIR_STRING(file) TARGET_DIR_HASH(file)
> > +#define TARGET_DIR(file) TARGET_DIR_STRING(TARGET_DIR_PREFIX/file)
> 
> Cool trick!  It seems pretty reasonable to me.
> 
> -- 
> Eric Blake, Principal Software Engineer
> Red Hat, Inc.           +1-919-301-3266
> Virtualization:  qemu.org | libvirt.org