So everything in Rawhide must be compiled with -fPIC?

[Richard W.M. Jones]

On Thu, Feb 19, 2015 at 11:45:01AM +0100, Jakub Jelinek wrote:
> On Thu, Feb 19, 2015 at 10:37:46AM +0000, Richard W.M. Jones wrote:
> > On Thu, Feb 19, 2015 at 11:35:17AM +0100, Jakub Jelinek wrote:
> > > On Thu, Feb 19, 2015 at 10:30:50AM +0000, Richard W.M. Jones wrote:
> > > > info gcc, of course yes.  -DPIC is not documented at all, and the
> > > > various pie/pic options are obscure to say the least.
> > > 
> > > Why should -DPIC be documented?  -D is documented.  -DPIC means define
> > > macro PIC to 1.  There is no magic in that beyond, just a convention,
> > > used e.g. by libtool, so that some sources can do things conditional on
> > > whether they are compiled as position independent or not.  Of course, gcc
> > > also predefines __pic__/__PIC__/__pie__/__PIE__ macros depending on command
> > > line options.
> > 
> > Can I ask you a simple question?  Which of:
> > 
> > -DPIE
> > -fPIE
> > -fpie
> > 
> > should I use when compiling and/or linking binaries for Rawhide?
> 
> It depends.  If you want to compile/link position independent binaries,
> use -fpie (-fPIE if you get linker errors on certain architectures if your
> binaries are too big) to compile and -pie to link.
> If you want normal binaries, no specific options in either case.
> If you want to follow the redhat-rpm-config %_hardened_build, i.e. build
> PIEs if it is 1 and normal binaries if it is 0, make sure you pass
> %{optflags} aka $RPM_OPT_FLAGS to the compiler driver when compiling and
> %{__global_ldflags} to the compiler driver when linking.
> Overriding CFLAGS/CXXFLAGS globally to -fpie or -fPIE and LDFLAGS to -pie
> if your package builds both binaries and shared libraries won't really work,
> because you might end up compiling shared library objects with -fpie rather
> than -fpic or try to link shared libraries with -shared -pie.

Thanks - I have linked this post to the BZ and closed it.

Rich.

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