[skip ci] Automatically update README.md

README.md

@@ -188,6 +188,7 @@ install-php-extensions @fix_letsencrypt
 | cmark |  |  | ✓ | ✓ | ✓ | ✓ | ✓ |  |  |  |
 | csv |  |  |  |  |  | ✓ | ✓ | ✓ | ✓ | ✓ |
 | dba | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
+| ddtrace[*](#special-requirements-for-ddtrace) |  |  | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |  |
 | decimal |  |  | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 | ds |  |  | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 | enchant | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
@@ -302,7 +303,7 @@ install-php-extensions @fix_letsencrypt
 | zookeeper | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |  |
 | zstd | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
 
-*Number of supported extensions: 124*
+*Number of supported extensions: 125*
 <!-- END OF EXTENSIONS TABLE -->
 
 PS: the pre-installed PHP extensions are excluded from this list.
@@ -383,6 +384,7 @@ Some extensions have special requirements:
 <!-- ########################################################### -->
 | Extension | Requirements |
 |---|---|
+| <a name="special-requirements-for-ddtrace"></a>ddtrace | &bull; Not available in `alpine3.7` docker images<br />&bull; Not available in `alpine3.8` docker images<br />&bull; Not available in `jessie` docker images |
 | <a name="special-requirements-for-geos"></a>geos | &bull; Not available in `alpine3.7` docker images<br />&bull; Not available in `alpine3.8` docker images<br />&bull; Not available in `alpine3.9` docker images<br />&bull; Not available in `alpine3.10` docker images |
 | <a name="special-requirements-for-memprof"></a>memprof | Not available in `alpine` docker images |
 | <a name="special-requirements-for-parallel"></a>parallel | Requires images with PHP compiled with thread-safety enabled (`zts`) |