Re: Incorrect use of SEC_MERGE in tc-ppc.c

[Elena Zannoni <ezannoni at redhat dot com>]

Jakub Jelinek writes:
 > Hi!
 > 
 > tc-ppc.c (ppc_cleanup) does:
 > 
 >     /* Create the .PPC.EMB.apuinfo section.  */
 >     apuinfo_secp = subseg_new (".PPC.EMB.apuinfo", 0);
 >     bfd_set_section_flags (stdoutput,
 >                            apuinfo_secp,
 >                            SEC_HAS_CONTENTS | SEC_READONLY | SEC_MERGE);
 > 
 > yet never sets apuinfo_secp->entsize.
 > This is wrong, every SHF_MERGE section must have non-zero sh_entsize,
 > either it is the size of each constant, or if SHF_STRINGS is set too
 > it is size of character in the strings.
 > As .PPC.EMB.apuinfo is not fixed size section, there is no suitable
 > entsize value though.
 > If you want to merge .PPC.EMB.apuinfo sections from a.o and b.o iff
 > they are the same size and have same content, then more work is needed,
 > like instead of creating .PPC.EMB.apuinfo section create
 > e.g. .PPC.EMB.apuinfo.<ppc_apuinfo_num> section with SEC_MERGE
 > and apuinfo_secp->entsize = 20 + ppc_apuinfo_num * 4.
 > Then also linker script needs to be tweaked, so that it has
 > .PPC.EMB.apuinfo : { *(.PPC.EMB.apuinfo .PPC.EMB.apuinfo.*) }
 > for non-relocatable build.
 > If some other merging is wanted instead, please explain what exactly.
 > 
 > 	Jakub

Sorry, I only committed the code. I'll see if I can do something about
it. The original author is, ahem..., 'unavailable for comments'.

Elena