1Extracted fix from postfix-3.8-20221006 snapshot:
2 https://github.com/vdukhovni/postfix/commit/b65530350fa4a7eee40946160fd80c3e1e0b63e5
3--- a/makedefs
4+++ b/makedefs
5@@ -627,7 +627,8 @@ EOF
6 : ${SHLIB_ENV="LD_LIBRARY_PATH=`pwd`/lib"}
7 : ${PLUGIN_LD="${CC-gcc} -shared"}
8 ;;
9- Linux.[345].*) SYSTYPE=LINUX$RELEASE_MAJOR
10+ Linux.[3456].*)
11+ SYSTYPE=LINUX$RELEASE_MAJOR
12 case "$CCARGS" in
13 *-DNO_DB*) ;;
14 *-DHAS_DB*) ;;
15--- a/src/util/sys_defs.h
16+++ b/src/util/sys_defs.h
17@@ -751,7 +751,8 @@ extern int initgroups(const char *, int);
18 /*
19 * LINUX.
20 */
21-#if defined(LINUX2) || defined(LINUX3) || defined(LINUX4) || defined(LINUX5)
22+#if defined(LINUX2) || defined(LINUX3) || defined(LINUX4) || defined(LINUX5) \
23+ || defined(LINUX6)
24 #define SUPPORTED
25 #define UINT32_TYPE unsigned int
26 #define UINT16_TYPE unsigned short