The php8 difference fixed identically at upstream:

[packages/php-pecl-zstd.git] / php8-argument.patch

https://github.com/kjdev/php-ext-zstd/commit/729d8401bfba37a3ee558cd051a1a525b5301dbd

002- ArgumentCountError: zstd_compress() expects at least 1 parameter, 0 given
002+ ArgumentCountError: zstd_compress() expects at least 1 argument, 0 given

--- php80-pecl-zstd-0.9.0/tests/002_b.phpt~	2020-06-04 08:14:49.000000000 +0300
+++ php80-pecl-zstd-0.9.0/tests/002_b.phpt	2021-01-03 11:18:38.017531735 +0200
@@ -29,7 +29,7 @@
 ===Done===
 --EXPECTF--
 *** Testing zstd_compress() function with Zero arguments ***
-ArgumentCountError: zstd_compress() expects at least 1 parameter, 0 given in %s:%d
+ArgumentCountError: zstd_compress() expects at least 1 %s, 0 given in %s:%d
 Stack trace:
 #0 %s(%d): zstd_compress()
 #1 {main}
--- php80-pecl-zstd-0.9.0/tests/005_b.phpt~	2020-06-04 08:14:49.000000000 +0300
+++ php80-pecl-zstd-0.9.0/tests/005_b.phpt	2021-01-03 11:19:37.230586143 +0200
@@ -33,7 +33,7 @@
 ===DONE===
 --EXPECTF--
 *** Testing zstd_uncompress() function with Zero arguments ***
-ArgumentCountError: zstd_uncompress() expects exactly 1 parameter, 0 given in %s:%d
+ArgumentCountError: zstd_uncompress() expects exactly 1 %s, 0 given in %s:%d
 Stack trace:
 #0 %s(%d): zstd_uncompress()
 #1 {main}