[PATCH v4] ld: Support LD_UNDER_TEST environment variable

[Nick Clifton]

Hi H.J.

> Support LD_UNDER_TEST environment variable to test a different linker.
> Issue an error if LD_UNDER_TEST isn't an absolute full path.

I would ask for one more change:

> +	perror "**************************************************"
> +	perror "$env(LD_UNDER_TEST) isn't an absolute full path."
> +	perror "**************************************************"

If I am reading this correctly the error message will show the contents
of the LD_UNDER_TEST environment variable, but not the name of the variable.
This could be confusing if the user does not realise that they have the
variable set.  Therefore please could you update the message to something
like:

   perror "Environment variable LD_UNDER_TEST ($env(LD_UNDER_TEST)) is not an absolute full path"

And similarly for the other error message.

Patch approved with these changes,.

Cheers
   Nick