[PATCH v3 1/9] Add configure check to test if gcc supports attribute ifunc.

[Florian Weimer]

On 08/24/2016 04:04 PM, Stefan Liebler wrote:
> +For multi-arch support it is recommended to use a GCC with gnu-indirect-function
> +support as it is used to generate ifunc'ed symbols with correct
> +debug-information. This support can either be enabled by configuring GCC with
> +@samp{--enable-gnu-indirect-function} or by enabling it by default by setting
> +@samp{default_gnu_indirect_function} variable for a particular architecture in
> +gcc source file @file{gcc/config.gcc}.

Maybe use this text instead?

For multi-arch support it is recommended to use a GCC which has been 
built with support for GNU indirect functions.  This ensures that 
correct debugging information is generated for functions selected by 
IFUNC resolvers.  This support can either be enabled by configuring GCC 
with @samp{--enable-gnu-indirect-function}, or by enabling it by default 
by setting @samp{default_gnu_indirect_function} variable for a 
particular architecture in the GCC source file @file{gcc/config.gcc}.


The configure check looks okay to me.  Some existing checks use 
AC_TRY_COMPILE, others use the manual expansion you provided.

Thanks,
Florian