[LLVMdev] __eh_frame info changes in Clang?

[Rafael Espíndola]

That looks like a bug.

From

http://www.linuxbase.org/betaspecs/lsb/LSB-Core-generic/LSB-Core-generic/ehframechpt.html

Version
A 1 byte value that identifies the version number of the frame
information structure. This value shall be 1.

This was introduced by r211272. We should probably be producing 1/3/4
for .debug_frame, but only 1 for .eh_frame.


On 10 April 2015 at 22:04, Jack Howarth <howarth.mailing.lists at gmail.com> wrote:
> Nick,
>       Do you happen to know why the version reported in 'dwarfdump
> --eh-frame' for object files now differs when compiled with and
> without -g? The test used in FSF gcc's configure produces a diff of..
>
> % diff -u conftest.o.g.stripped.dwarfdump conftest.o.g0.stripped.dwarfdump
> --- conftest.o.g.stripped.dwarfdump 2015-04-10 21:43:15.000000000 -0400
> +++ conftest.o.g0.stripped.dwarfdump 2015-04-10 21:43:04.000000000 -0400
> @@ -1,5 +1,5 @@
>  ----------------------------------------------------------------------
> - File: conftest.o.g.stripped (x86_64)
> + File: conftest.o.g0.stripped (x86_64)
>  ----------------------------------------------------------------------
>  Exception handling frame information for section __eh_frame
>
> when compiled with Clang 6.0 (3.5svn) but now produces...
>
> % diff -u conftest.o.g.stripped.dwarfdump conftest.o.g0.stripped.dwarfdump
> --- conftest.o.g.stripped.dwarfdump 2015-04-10 21:42:02.000000000 -0400
> +++ conftest.o.g0.stripped.dwarfdump 2015-04-10 21:41:52.000000000 -0400
> @@ -1,12 +1,12 @@
>  ----------------------------------------------------------------------
> - File: conftest.o.g.stripped (x86_64)
> + File: conftest.o.g0.stripped (x86_64)
>  ----------------------------------------------------------------------
>  Exception handling frame information for section __eh_frame
>
>  0x00000000: CIE
>          length: 0x00000014
>          CIE_id: 0xffffffff
> -       version: 0x01
> +       version: 0x03
>    augmentation: "zR"
>      code_align: 1
>      data_align: -8
>
> when compiled with Clang 6.1 (3.6.0svn) or llvm.org clang 3.6.0. The
> detailed steps to obtain those test files are listed at
> https://llvm.org/bugs/show_bug.cgi?id=23192.
>          Jack
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