A common convention is to name internal C header files as `*_int.h`.
Since a couple of these are actually installed, we add comments that
this is not supposed to happen, (a) to avoid installing further
internal headers, and (b) to pave the way to fix this in the next major
PHP version.
Somewhat special is php_gmp_int.h, where "int" is meant as abbreviation
for "interface".
Another common convention is appending `_priv` or `_private`, but since
there have not been any issues regarding these headers so far, we
refrain from adding respective comments to these headers.
Anyhow, it might be a good idea to introduce some common naming
convention for such internal/private headers.
`zend_strtod.c` uses a global state (mostly an allocation freelist) protected by a mutex in ZTS builds. This state is used by `zend_dtoa()`, `zend_strtod()`, and variants. This creates a lot of contention in concurrent loads. `zend_dtoa()` is used to format floats to string, e.g. in sprintf, json_encode, serialize, uniqid.
Here I move the global state to the thread specific `executor_globals` and remove the mutex.
The impact on non-concurrent environments is null or negligible, but there is a considerable speed up on concurrent environments, especially on Alpine/Musl.
These are mandatory in C99, so it's a pointless waste of time to check
for them.
(Actually, the fixed-size integer types are not mandatory, but if they
are really not available on some theoretical system, PHP's fallbacks
won't work either, so nothing is gained from this check.)
This patch removes the so called local variables defined per
file basis for certain editors to properly show tab width, and
similar settings. These are mainly used by Vim and Emacs editors
yet with recent changes the once working definitions don't work
anymore in Vim without custom plugins or additional configuration.
Neither are these settings synced across the PHP code base.
A simpler and better approach is EditorConfig and fixing code
using some code style fixing tools in the future instead.
This patch also removes the so called modelines for Vim. Modelines
allow Vim editor specifically to set some editor configuration such as
syntax highlighting, indentation style and tab width to be set in the
first line or the last 5 lines per file basis. Since the php test
files have syntax highlighting already set in most editors properly and
EditorConfig takes care of the indentation settings, this patch removes
these as well for the Vim 6.0 and newer versions.
With the removal of local variables for certain editors such as
Emacs and Vim, the footer is also probably not needed anymore when
creating extensions using ext_skel.php script.
Additionally, Vim modelines for setting php syntax and some editor
settings has been removed from some *.phpt files. All these are
mostly not relevant for phpt files neither work properly in the
middle of the file.
The special cases (float)"inf", etc. were never intended and are
caused by the updated strtod lib. While it might be nice as an
easy way to produce Inf and NaN special values, it was never
documented and cause BC breaches.
