On Monday, 6 January 2014 at 18:59:00 UTC, Iain Buclaw wrote:
On 6 Jan 2014 13:45, "Dicebot" <pub...@dicebot.lv> wrote:
On Friday, 3 January 2014 at 18:14:58 UTC, Mike wrote:
I eventually tracked it down to the fact that I was compiling
with
-ffunction-sections and -fdata-sections and linking with
--gc-sections and
symbols like...
I never got --gc-sections to work reliably with D without
going dirty,
crashes were somewhat common for any non-trivial program. Don't
think this
particular use case is tested by anyone at all, you are on your
own once
you get here.
Of course ! --gc-sections is just a dirty hack. If you want
smaller
binaries, then you are better off aiding the shared library
support. :)
I don't ever recall any of the core maintainers ever endorsing
that switch
anyway....
I agree that the --gc-sections method is hackish, but I wouldn't
say it's dirty. And, in absence of a better method, it is
*essential* in the embedded world, and was likely added
specifically to make the GNU toolchain a feasible alternative for
the embedded market. I doubt the Arduino, with its 32KB of flash
memory, would have even been created without it.
The STM32 processors that I use have 16 ~ 1024KB of flash on
them, and --gc-sections is essential to get some programs to fit.
Furthermore, it saves my employer 10s of thousands of dollars in
hardware costs for mass produced devices. With --gc-sections,
these devices can be built with C/C++, libsup++, newlib, and
libc++ quite effectively. Without it, this would be impossible.
Shared library support just doesn't apply in this world. Most of
the devices I build are single-threaded, and much of code in the
libraries is just never called, and hacking the library's source
code with #defines to strip out stuff is a non-solution.
I'm interested in knowing why --gc-sections works well for C/C++
programs but not D, and I hope the compilers will eventually emit
code that can support it.
It would be sad if D fragmented into D and embedded-D. I don't
think that would serve the D language well.
I'm liking D so far, and I'm very interested in seeing D become
an alternative for the embedded world. I'm willing to help in
any way I can.
