From e0ccfea0274b3830501175db262b5f42642ca273 Mon Sep 17 00:00:00 2001
From: orbitcowboy <orbitcowboy@web.de>
Date: Sun, 1 May 2022 15:29:35 +0200
Subject: [PATCH] gnu.cfg: Improved configuration of ffsl() and ffsll()

---
 cfg/gnu.cfg      |  3 ++-
 test/cfg/gnu.c   | 20 ++++++++++++++++++++
 test/cfg/posix.c |  2 +-
 3 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/cfg/gnu.cfg b/cfg/gnu.cfg
index 675c4f896..7cb66e5ce 100644
--- a/cfg/gnu.cfg
+++ b/cfg/gnu.cfg
@@ -1161,7 +1161,8 @@
        int ffsll(long long int i); -->
   <function name="ffsl,ffsll">
     <use-retval/>
-    <returnValue type="int"/>
+    <!-- It returns the position of the first bit set, or 0 if no bits are set in i. -->
+    <returnValue type="int">arg1==0 &amp;0</returnValue>
     <noreturn>false</noreturn>
     <leak-ignore/>
     <arg nr="1" direction="in">
diff --git a/test/cfg/gnu.c b/test/cfg/gnu.c
index 5690b126a..545ef8cad 100644
--- a/test/cfg/gnu.c
+++ b/test/cfg/gnu.c
@@ -22,6 +22,26 @@
 #include <sys/epoll.h>
 #endif
 
+#include <strings.h>
+
+void knownConditionTrueFalse_ffsl(long i)
+{
+    // ffs() returns the position of the first bit set, or 0 if no bits are set in i.
+    const int x = ffsl(0);
+    // cppcheck-suppress knownConditionTrueFalse
+    if (x == 0) {}
+    if (ffsl(i) == 0) {}
+}
+
+void knownConditionTrueFalse_ffsll(long long i)
+{
+    // ffs() returns the position of the first bit set, or 0 if no bits are set in i.
+    const int x = ffsll(0);
+    // cppcheck-suppress knownConditionTrueFalse
+    if (x == 0) {}
+    if (ffsll(i) == 0) {}
+}
+
 int nullPointer_semtimedop(int semid, struct sembuf *sops, size_t nsops, const struct timespec *timeout)
 {
     (void) semtimedop(semid, sops, nsops, NULL); // If the timeout argument is NULL, then semtimedop() behaves exactly like semop().
diff --git a/test/cfg/posix.c b/test/cfg/posix.c
index e6bc4dedb..6b2d13fb4 100644
--- a/test/cfg/posix.c
+++ b/test/cfg/posix.c
@@ -31,8 +31,8 @@
 #define _XOPEN_SOURCE
 #include <wchar.h>
 #include <string.h>
-
 #include <strings.h>
+
 void knownConditionTrueFalse_ffs(int i)
 {
     // ffs() returns the position of the first bit set, or 0 if no bits are set in i.