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busybox Unused variable if MDEV_CONF && MDEV_RENAME && !MDEV_RENAME_REGEXP. The pointer variable *p is unused when MDEV_CONF and MDEV_RENAME are set and MDEV_RENAME_REGEXP is not defined.

Bug fixed by commit b62bd7b261b

Type	UnusedVariable
Config	FEATURE_MDEV_CONF && FEATURE_MDEV_RENAME && !FEATURE_MDEV_RENAME_REGEXP (3rd degree)
C-features	PointerArithmetic
Fix-in	mapping
Location	util-linux/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

void make_device()
{
#ifdef ENABLE_FEATURE_MDEV_CONF

#ifdef ENABLE_FEATURE_MDEV_RENAME
  char *val;
  char *s, *p;
  val = "mode - device permissions";
  
  char *a = val;
  s = strchr(val, ' ');
  val = (s && s[1]) ? s+1 : NULL;
  
#ifdef ENABLE_FEATURE_MDEV_RENAME_REGEXP
  /* substitute %1..9 with off[1..9], if any */
  int n = 0;
  s = a;
  
  while (*s) {
    *p = *s;
    
    if(rand() % 2) {
      n++;
      p += n - 1;
    }
    
    p++;
    s++;
  }
#endif

#endif /* ENABLE_FEATURE_MDEV_RENAME */

#endif
}

int main(int argc, char** argv)
{
  if(rand() % 2)
    make_device();
  return 0;
}

diff --git a/simple/b62bd7b.c b/simple/b62bd7b.c
--- a/simple/b62bd7b.c
+++ b/simple/b62bd7b.c
@@ -9,7 +9,10 @@
 
 #ifdef ENABLE_FEATURE_MDEV_RENAME
   char *val;
-  char *s, *p;
+  char *s; 
+#ifdef ENABLE_FEATURE_MDEV_RENAME_REGEXP  
+  char *p;
+#endif  
   val = "mode - device permissions";
   
   char *a = val;

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(int argc, char** argv)
{
  if(rand() % 2) {
//    make_device();
#ifdef ENABLE_FEATURE_MDEV_CONF

#ifdef ENABLE_FEATURE_MDEV_RENAME
    char *val;
    char *s, *p;
    val = "mode - device permissions";
  
    char *a = val;
    s = strchr(val, ' ');
    val = (s && s[1]) ? s+1 : NULL;
  
#ifdef ENABLE_FEATURE_MDEV_RENAME_REGEXP
  /* substitute %1..9 with off[1..9], if any */
    int n = 0;
    s = a;
  
    while (*s) {
      *p = *s;
    
      if(rand() % 2) {
        n++;
        p += n - 1;
      }
    
      p++;
      s++;
    }
#endif

#endif /* ENABLE_FEATURE_MDEV_RENAME */

#endif
  }
  return 0;
}