On 19.03.2025 12:58, Marek Marczykowski-Górecki wrote: > On Wed, Mar 19, 2025 at 10:43:12AM +0100, Jan Beulich wrote: >> On 19.03.2025 10:15, Jan Beulich wrote: >>> On 18.03.2025 18:01, Marek Marczykowski-Górecki wrote: >>>> --- a/xen/Makefile >>>> +++ b/xen/Makefile >>>> @@ -411,6 +411,8 @@ ifneq ($(CONFIG_CC_IS_CLANG),y) >>>> CFLAGS += -Wa,--strip-local-absolute >>>> endif >>>> >>>> +$(call cc-option-add CFLAGS,CC,-ffile-prefix-map=$(XEN_ROOT)=.) >>> >>> This is lacking a comma: >>> >>> $(call cc-option-add,CFLAGS,CC,-ffile-prefix-map=$(XEN_ROOT)=.) >> >> And then, having tried the correct form (seeing the option then is passed >> to the compiler), I can't spot any difference in the resulting >> xen-syms.map. There were a few absolute paths there before (for >> arch/x86/x86_64/kexec_reloc.S and arch/x86/acpi/wakeup_prot.S), and the >> exact same ones are present afterwards. > > I'm not sure about xen-syms.map, it's about build path included in > xen-syms. It appears at least once in .debug_str and once in > .debug_line_str.
In which case -fdebug-prefix-map= may suffice, which is available on more compiler versions? And then only if DEBUG_INFO=y? > But also, I see the patch lost a chunk during rebase (from before > 4.17...), that adjusts XEN_ROOT to use $(realpath ...). That's the part > even mentioned in the commit message... > > I'll send v2 shortly. Provided there's actually a need. I was in fact wondering whether this was known to have significant effect prior to Anthony's work to make out-of-tree builds possible (plus less related adjustments), but may have lost most of its functionality since then (yet was still carried forward for all the time). Jan
