Re: [PATCH 3/3][DejaGNU] target: Wrap linker flags into `-largs'/`-margs' for Ada

[Maciej W. Rozycki]

On Wed, 15 May 2019, Jacob Bachmeyer wrote:

> This patch really exposes a significant deficiency in our current 
> implementation of default_target_compile:  the order of various flags 
> can be significant, but we only have that order implicitly expressed in 
> the code, which goes all the way back to (of course) the "Initial 
> revision" that is probably from a time before Tcl had the features that 
> will allow significant cleanup in here.

 I suspect the origins may be different, however as valuable as your 
observation is functional problems have precedence over issues with code 
structuring, so we need to fix the problem at hand first.  I'm sure 
DejaGNU maintainers will be happy to review your implementation of code 
restructuring afterwards.

> Some of these could probably be combined and I may have combined 
> categories that should be separate in the above list.  The GNU toolchain 
> has always been a kind of "magic box that just works" (until it doesn't 
> and the manual explains the problem) for me, so I am uncertain what the 
> ordering rules for combining these categories should be.  Anyone know 
> the traditional rules and, perhaps more importantly, what systems need 
> which rules?

 The ordering rules are system-specific I'm afraid and we have to be 
careful not to break working systems out there.  People may be forced to a 
DejaGNU upgrate, due to a newer version of a program being tested having 
such a requirement, and can legitimately expect their system to continue 
working.

 NB I have been repeatedly observing cases where a forced upgrade of a 
system component I neither care nor I am competent about, triggered by an 
upgrade of a component I do care about, caused the system to malfunction 
in a way that I find both unacceptable and extremely hard to debug.  It 
seems to have become more frequent in the recent years, and I find this 
both very frustrating and have wasted lots of time trying to fix the 
damage caused.  I would therefore suggest to take all the measures 
possible to save people from going through such an experience.

 FWIW,

  Maciej