[PATCH 1/2] Use -fno-asynchronous-unwind-tables if C program is compiled without debug info on x86

[Pedro Alves]

I think the subject would be clearer if it mentioned this is about gdb tests.  E.g.:

Use -fno-asynchronous-unwind-tables on x86 for gdb C tests without debug info

On 04/19/2016 08:50 AM, Yao Qi wrote:
> .eh_frame is added in default on x86 and x86_64 so that DWARF unwinder
> is always used, but prologue unwinders won't be used at all.  IOW,
> prologue unwinders are not tested by regression tests.  If the test is
> intended to compiled *without* debug info, we shouldn't generate any
> debug info (.eh_frame for example) at all.
> 
> This patch is to disable async-unwind-tables generation if the C program
> is intended to compile without debug info on x86-like target.

No sure about this.  This is an ABI change on x86_64 -- the x86_64 ABI
requires eh_frame.

Should we instead add a new "nounwind" option, and a few
prologue-unwinder-specific tests?

Thanks,
Pedro Alves