From: Mike Gilbert <floppym@gentoo.org>
Date: Mon, 14 Sep 2015 22:55:09 +0000 (-0400)
Subject: Add fallback for kcmp() in case __NR_kcmp is undefined
X-Git-Tag: v227.2^2~34
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=commitdiff_plain;h=f95cf7a0e475fcb8777c43081219320f7e3dc59b;hp=01bdc7e671164ba3126b135a475a05b6f27f985c

Add fallback for kcmp() in case __NR_kcmp is undefined

IA64 is missing this syscall as of linux-4.2.
This works around it until the necessary kernel patch gets merged.
---

diff --git a/src/basic/missing.h b/src/basic/missing.h
index bc6fbc539..a073e89da 100644
--- a/src/basic/missing.h
+++ b/src/basic/missing.h
@@ -1026,7 +1026,12 @@ static inline int renameat2(int oldfd, const char *oldname, int newfd, const cha
 
 #if !HAVE_DECL_KCMP
 static inline int kcmp(pid_t pid1, pid_t pid2, int type, unsigned long idx1, unsigned long idx2) {
+#if defined(__NR_kcmp)
         return syscall(__NR_kcmp, pid1, pid2, type, idx1, idx2);
+#else
+        errno = ENOSYS;
+        return -1;
+#endif
 }
 #endif