Hi Segher, On Wed, 2018-11-28 at 15:00 -0600, Segher Boessenkool wrote: > On Tue, Nov 27, 2018 at 08:54:07PM +0100, Mark Wielaard wrote: > > On Tue, 2018-11-27 at 12:37 -0600, Segher Boessenkool wrote: > > > > Define a new target macro TARGET_HAS_DEFAULT_NOEXEC_STACK for > > > > those > > > > targets > > > > that have a non-executable default stack based on when they > > > > call > > > > file_end_indicate_exec_stack. > > > > > > As Paul says, that name isn't so good. > > > > > > TARGET_NEEDS_MAKING_THE_STACK_EXECUTABLE_FOR_TRAMPOLINES, or > > > similar? > > > > Would the slightly shorter > > TARGET_NEEDS_EXEC_STACK_MARKER_FOR_TRAMPOLINES be descriptive > > enough? > > "MARKER", is that some official name for it? If no, just "FLAG"? > Fine with me, sure.
FLAG it is then! It is even a little shorter :) > > > > diff --git a/gcc/config/rs6000/sysv4.h > > > > b/gcc/config/rs6000/sysv4.h > > > > index 0c67634..9330acf 100644 > > > > --- a/gcc/config/rs6000/sysv4.h > > > > +++ b/gcc/config/rs6000/sysv4.h > > > > @@ -972,6 +972,11 @@ ncrtn.o%s" > > > > /* Generate entries in .fixup for relocatable addresses. */ > > > > #define RELOCATABLE_NEEDS_FIXUP 1 > > > > > > > > +#if defined (POWERPC_LINUX) || defined (POWERPC_FREEBSD) > > > > + #define TARGET_HAS_DEFAULT_NOEXEC_STACK (TARGET_32BIT \ > > > > + || DEFAULT_ABI == > > > > ABI_ELFv2) > > > > +#endif > > > > > > I don't think this belongs in sysv4.h . > > > > I might have gotten lost in the tree of defines/macros. > > > > There are two sysv4.h files gcc/config/rs6000/sysv4.h and > > gcc/config/powerpcspe/sysv4.h > > Forget about powerpcspe please, I am talking about rs6000 only. I don't know the differences between the config backends, but it looks like at least some of the configs were just copy/pasted which might explain why they both define things the same (in sysv4.h). And they both use the same TARGET_ASM_FILE_END hook (set to rs6000_elf_file_end although that function also seems copy/pasted between powerpcspe.c and rs6000.c. Could you explain why I should forget about powerpcspe and/or why where and how to setup the new target marco would be different between the two config backends? > You want linux.h and freebsd.h, maybe the "64" versions of those separately. > Or put this in rs6000.h. sysv4.h is a random header for this, it doesn't > belong there. The reason I added it to sysv4.h is because it matches where the TARGET_ASM_FILE_END hook is setup. It might make sense to have specialized TARGET_ASM_FILE_END hooks too for [linux,freebsd)(64)].h. But that is probably a different discussion. So if I understand correctly you would like to have: rs6000/linux.h and rs6000/freebsd.h: #define TARGET_NEEDS_EXEC_STACK_FLAG_FOR_TRAMPOLINES 1 rs6000/linux64.h and rs6000/freebsd64.h: #define TARGET_NEEDS_EXEC_STACK_FLAG_FOR_TRAMPOLINES (DEFAULT_ABI == ABI_ELFv2) If so, shouldn't the same be done for powerpcspe? Sorry, you told me to forget about it, but I just cannot :) Thanks, Mark
