Sent from my mobile
On 15 Jan 2019, at 15:29, Christoph M. Becker
<cmbecke...@gmx.de<mailto:cmbecke...@gmx.de>> wrote:
On 15.01.2019 at 13:32, Zeev Suraski wrote:
On 15 Jan 2019, at 13:13, Christoph M. Becker
<cmbecke...@gmx.de<mailto:cmbecke...@gmx.de>> wrote:
Most recently, a pull request has been submitted for libgd[1], which
suggests to define image IO functions for several image formats
unconditionally; if the format is not supported, the IO functions would
fail with an error notice. This would break the current ext/gd
configuration, since it relies on checks for the existence of these
functions[2] to define the respective PHP functions conditionally and
for introspection (e.g. gd_info()). In other words, building ext/gd
against the PR would define imagecreatefromweb() even if WebP is not
supported. This would break code relying on `if
(function_exists('imagecreatefromweb'))` or such.
Given this downside, what is the upside of introducing this change?
Basically, to be able to switch libgd.so without recompiling its
clients, see
<https://github.com/libgd/libgd/issues/345#issuecomment-454148489>. Of
course, that wouldn't work for ext/gd as it is now, but that is a
different story. We have to deal with whatever the libgd developers decide.
If that's the reason - I believe it should be possible to retain the current
behavior and also get the benefit of being able to replace the underlying
library. I think we can just register the relevant functions dynamically in
MINIT based on what's available in runtime.
I've seen the pattern of using function_exists() to determine whether or not a
given format is supported in numerous places over the years, so I think we
should avoid breaking it.
Zeev
