GNU utilities cannot necessarily parse objects built by LLVM, which can
result in confusing errors when using 'faddr2line':
$ CROSS_COMPILE=aarch64-linux-gnu- ./scripts/faddr2line vmlinux do_one_initcall+0xf4/0x260
aarch64-linux-gnu-addr2line: vmlinux: unknown type [0x13] section `.relr.dyn'
aarch64-linux-gnu-addr2line: DWARF error: invalid or unhandled FORM value: 0x25
do_one_initcall+0xf4/0x260:
aarch64-linux-gnu-addr2line: vmlinux: unknown type [0x13] section `.relr.dyn'
aarch64-linux-gnu-addr2line: DWARF error: invalid or unhandled FORM value: 0x25
$x.73 at main.c:?
Although this can be worked around by setting CROSS_COMPILE to "llvm=-",
it's cleaner to follow the same syntax as the top-level Makefile and
accept LLVM=1 as an indication to use the llvm- tools.
Cc: Josh Poimboeuf <[email protected]>
Cc: John Stultz <[email protected]>
Signed-off-by: Will Deacon <[email protected]>
---
scripts/faddr2line | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/scripts/faddr2line b/scripts/faddr2line
index 0e73aca4f908..62a3fa6f6f59 100755
--- a/scripts/faddr2line
+++ b/scripts/faddr2line
@@ -58,8 +58,14 @@ die() {
exit 1
}
-READELF="${CROSS_COMPILE:-}readelf"
-ADDR2LINE="${CROSS_COMPILE:-}addr2line"
+if [ "${LLVM:-}" == "1" ]; then
+ UTIL_PREFIX=llvm-
+else
+ UTIL_PREFIX=${CROSS_COMPILE:-}
+fi
+
+READELF="${UTIL_PREFIX}readelf"
+ADDR2LINE="${UTIL_PREFIX}addr2line"
AWK="awk"
GREP="grep"
--
2.41.0.487.g6d72f3e995-goog
On Fri, Jul 28, 2023 at 8:34 PM Will Deacon <[email protected]> wrote:
>
> GNU utilities cannot necessarily parse objects built by LLVM, which can
> result in confusing errors when using 'faddr2line':
>
> $ CROSS_COMPILE=aarch64-linux-gnu- ./scripts/faddr2line vmlinux do_one_initcall+0xf4/0x260
> aarch64-linux-gnu-addr2line: vmlinux: unknown type [0x13] section `.relr.dyn'
> aarch64-linux-gnu-addr2line: DWARF error: invalid or unhandled FORM value: 0x25
> do_one_initcall+0xf4/0x260:
> aarch64-linux-gnu-addr2line: vmlinux: unknown type [0x13] section `.relr.dyn'
> aarch64-linux-gnu-addr2line: DWARF error: invalid or unhandled FORM value: 0x25
> $x.73 at main.c:?
>
> Although this can be worked around by setting CROSS_COMPILE to "llvm=-",
> it's cleaner to follow the same syntax as the top-level Makefile and
> accept LLVM=1 as an indication to use the llvm- tools.
Just a note.
The top Makefile accepts not only LLVM=1
but also LLVM=/usr/lib/llvm-16/bin/.
The latter is useful when you want to use
a particular version or a custom one.
Another idea might be to use a generic '${prefix}'
as this is not hooked to the Makefile,
but I do not have a strong opinion.
>
> Cc: Josh Poimboeuf <[email protected]>
> Cc: John Stultz <[email protected]>
> Signed-off-by: Will Deacon <[email protected]>
> ---
> scripts/faddr2line | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/scripts/faddr2line b/scripts/faddr2line
> index 0e73aca4f908..62a3fa6f6f59 100755
> --- a/scripts/faddr2line
> +++ b/scripts/faddr2line
> @@ -58,8 +58,14 @@ die() {
> exit 1
> }
>
> -READELF="${CROSS_COMPILE:-}readelf"
> -ADDR2LINE="${CROSS_COMPILE:-}addr2line"
> +if [ "${LLVM:-}" == "1" ]; then
> + UTIL_PREFIX=llvm-
> +else
> + UTIL_PREFIX=${CROSS_COMPILE:-}
> +fi
> +
> +READELF="${UTIL_PREFIX}readelf"
> +ADDR2LINE="${UTIL_PREFIX}addr2line"
> AWK="awk"
> GREP="grep"
>
> --
> 2.41.0.487.g6d72f3e995-goog
>
--
Best Regards
Masahiro Yamada
On Sat, Jul 29, 2023 at 1:48 PM Masahiro Yamada <[email protected]> wrote:
>
> On Fri, Jul 28, 2023 at 8:34 PM Will Deacon <[email protected]> wrote:
> >
> > GNU utilities cannot necessarily parse objects built by LLVM, which can
> > result in confusing errors when using 'faddr2line':
> >
> > $ CROSS_COMPILE=aarch64-linux-gnu- ./scripts/faddr2line vmlinux do_one_initcall+0xf4/0x260
> > aarch64-linux-gnu-addr2line: vmlinux: unknown type [0x13] section `.relr.dyn'
^ old GNU binutils missing support for RELR relocation format.
https://maskray.me/blog/2021-10-31-relative-relocations-and-relr
> > aarch64-linux-gnu-addr2line: DWARF error: invalid or unhandled FORM value: 0x25
^ old GNU binutils missing support for DWARFv5
I suppose if someone used a new GCC with an old binutils, they could
observe the exact same errors.
> > do_one_initcall+0xf4/0x260:
> > aarch64-linux-gnu-addr2line: vmlinux: unknown type [0x13] section `.relr.dyn'
> > aarch64-linux-gnu-addr2line: DWARF error: invalid or unhandled FORM value: 0x25
> > $x.73 at main.c:?
> >
> > Although this can be worked around by setting CROSS_COMPILE to "llvm=-",
> > it's cleaner to follow the same syntax as the top-level Makefile and
> > accept LLVM=1 as an indication to use the llvm- tools.
>
>
> Just a note.
> The top Makefile accepts not only LLVM=1
> but also LLVM=/usr/lib/llvm-16/bin/.
> The latter is useful when you want to use
> a particular version or a custom one.
Ah, like LLVM_PREFIX/LLVM_SUFFIX a la
commit e9c281928c24 ("kbuild: Make $(LLVM) more flexible")
Then we could have both UTIL_PREFIX+UTIL_SUFFIX.
>
> Another idea might be to use a generic '${prefix}'
> as this is not hooked to the Makefile,
> but I do not have a strong opinion.
>
>
>
>
> >
> > Cc: Josh Poimboeuf <[email protected]>
> > Cc: John Stultz <[email protected]>
> > Signed-off-by: Will Deacon <[email protected]>
> > ---
> > scripts/faddr2line | 10 ++++++++--
> > 1 file changed, 8 insertions(+), 2 deletions(-)
> >
> > diff --git a/scripts/faddr2line b/scripts/faddr2line
> > index 0e73aca4f908..62a3fa6f6f59 100755
> > --- a/scripts/faddr2line
> > +++ b/scripts/faddr2line
> > @@ -58,8 +58,14 @@ die() {
> > exit 1
> > }
> >
> > -READELF="${CROSS_COMPILE:-}readelf"
> > -ADDR2LINE="${CROSS_COMPILE:-}addr2line"
> > +if [ "${LLVM:-}" == "1" ]; then
> > + UTIL_PREFIX=llvm-
> > +else
> > + UTIL_PREFIX=${CROSS_COMPILE:-}
> > +fi
> > +
> > +READELF="${UTIL_PREFIX}readelf"
> > +ADDR2LINE="${UTIL_PREFIX}addr2line"
> > AWK="awk"
> > GREP="grep"
> >
> > --
> > 2.41.0.487.g6d72f3e995-goog
> >
>
>
> --
> Best Regards
> Masahiro Yamada
--
Thanks,
~Nick Desaulniers