diff --git a/configure.ac b/configure.ac
index f01cb5379f8..ff96b307d69 100644
--- a/configure.ac
+++ b/configure.ac
@@ -237,7 +237,7 @@ esac
 
 dnl Detect musl libc
 AC_MSG_CHECKING([whether we are using musl libc])
-if command -v ldd >/dev/null && ldd --version 2>&1 | grep -q ^musl
+if command -v ldd >/dev/null && ldd --version 2>&1 | grep ^musl >/dev/null 2>&1
 then
   AC_MSG_RESULT([yes])
   AC_DEFINE([__MUSL__], [1], [Define to 1 when using musl libc.])
diff --git a/ext/posix/config.m4 b/ext/posix/config.m4
index ac70068bac8..b7a6e427725 100644
--- a/ext/posix/config.m4
+++ b/ext/posix/config.m4
@@ -43,7 +43,8 @@ if test "$PHP_POSIX" = "yes"; then
 
 dnl Skip pathconf and fpathconf check on musl libc due to limited implementation
 dnl (first argument is not validated and has different error).
-  AS_IF([command -v ldd >/dev/null && ldd --version 2>&1 | grep -q "^musl"],[],
+  AS_IF([command -v ldd >/dev/null && ldd --version 2>&1 | grep ^musl >/dev/null 2>&1],
+    [],
     [AC_CHECK_FUNCS([pathconf fpathconf])])
 
   AC_CACHE_CHECK([for working ttyname_r() implementation],