[Qemu-devel] [PATCH v3 9/9] checkpatch: complain about ffs(3) calls

[Stefan Hajnoczi <stefanha@redhat.com>]

The ffs(3) family of functions is not portable.  MinGW doesn't always
provide the function.

Use ctz32() or ctz64() instead.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 scripts/checkpatch.pl | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 5df61f9..7f0aae9 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2911,6 +2911,17 @@ sub process {
 		if ($rawline =~ /\b(?:Qemu|QEmu)\b/) {
 			WARN("use QEMU instead of Qemu or QEmu\n" . $herecurr);
 		}
+
+# check for non-portable ffs() calls that have portable alternatives in QEMU
+		if ($line =~ /\bffs\(/) {
+			ERROR("use ctz32() instead of ffs()\n" . $herecurr);
+		}
+		if ($line =~ /\bffsl\(/) {
+			ERROR("use ctz32() or ctz64() instead of ffsl()\n" . $herecurr);
+		}
+		if ($line =~ /\bffsll\(/) {
+			ERROR("use ctz64() instead of ffsll()\n" . $herecurr);
+		}
 	}
 
 	# If we have no input at all, then there is nothing to report on
-- 
2.1.0