--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gcc.dg/pr90037.c	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,161 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -Wnull-dereference" } */
+
+typedef __SIZE_TYPE__ size_t;
+typedef unsigned long int uintmax_t;
+
+struct group
+{
+  char *gr_name;
+  char *gr_passwd;
+  unsigned gr_gid;
+  char **gr_mem;
+};
+
+struct passwd
+{
+  char *pw_name;
+  char *pw_passwd;
+
+  unsigned pw_uid;
+  unsigned pw_gid;
+  char *pw_gecos;
+  char *pw_dir;
+  char *pw_shell;
+};
+
+extern struct group *getgrnam (const char *);
+extern struct group *getgrgid (unsigned);
+extern void endgrent (void);
+extern struct passwd *getpwnam (const char *);
+extern void endpwent (void);
+extern unsigned long int strtoul (const char *__restrict,
+				  char **__restrict, int);
+
+char const *
+parse_with_separator (char const *spec, char const *separator,
+                      unsigned *uid, unsigned *gid,
+                      char **username, char **groupname)
+{
+  static const char *E_invalid_user = "invalid user";
+  static const char *E_invalid_group = "invalid group";
+  static const char *E_bad_spec = "invalid spec";
+  const char *error_msg;
+  struct passwd *pwd;
+  struct group *grp;
+  char *u;
+  char const *g;
+  char *gname = 0;
+  unsigned unum = *uid;
+  unsigned gnum = gid ? *gid : (unsigned)-1;
+
+  error_msg = 0;
+
+  if (username)
+    *username = 0;
+
+  if (groupname)
+    *groupname = 0;
+
+  u = 0;
+  if (separator == 0)
+    {
+      if (*spec)
+        u = __builtin_strdup (spec);
+    }
+  else
+    {
+      size_t ulen = separator - spec;
+      if (ulen != 0)
+        {
+          u = __builtin_malloc (ulen + 1);
+          __builtin_memcpy (u, spec, ulen + 1);
+          u[ulen] = '\0';
+        }
+    }
+
+  g = (separator == 0 || *(separator + 1) == '\0' ? 0 : separator + 1);
+
+  if (u != 0)
+    {
+      pwd = (*u == '+' ? 0 : getpwnam (u));
+      if (pwd == 0)
+        {
+	  _Bool use_login_group = (separator != 0 && g == 0);
+          if (use_login_group)
+            {
+              error_msg = E_bad_spec;
+            }
+          else
+            {
+              unsigned long int tmp;
+              tmp = strtoul (u, 0, 10);
+              if (tmp <= (1ul << 31) && (unsigned) tmp != (unsigned) -1)
+                unum = tmp;
+              else
+                error_msg = E_invalid_user;
+            }
+        }
+      else
+        {
+          unum = pwd->pw_uid;
+          if (g == 0 && separator != 0)
+            {
+              char buf[128];
+              gnum = pwd->pw_gid;
+              grp = getgrgid (gnum);
+
+              gname = buf;
+
+              if (grp)
+		gname = __builtin_strdup (grp->gr_name);
+              else
+		__builtin_snprintf (buf, sizeof(buf), "%ju", (uintmax_t)gnum);
+
+              endgrent ();
+            }
+        }
+
+      endpwent ();
+    }
+
+  if (g != 0 && error_msg == 0)
+    {
+      grp = (*g == '+' ? 0 : getgrnam (g));
+      if (grp == 0)
+        {
+	  unsigned long int tmp = strtoul (g, 0, 10);
+		
+	  if (tmp <= (1ul << 31) && (unsigned) tmp != (unsigned) -1)
+            gnum = tmp;
+          else
+            error_msg = E_invalid_group;
+        }
+      else
+        gnum = grp->gr_gid;
+      endgrent ();
+      gname = __builtin_strdup (g);
+    }
+
+  if (error_msg == 0)
+    {
+      *uid = unum;
+      if (gid)
+        *gid = gnum;
+      if (username)
+        {
+          *username = u;
+          u = 0;
+        }
+      if (groupname)
+        {
+          *groupname = gname;
+          gname = 0;
+        }
+    }
+
+  __builtin_free (u);
+  __builtin_free (gname);
+  return error_msg ? error_msg : 0;
+}
+