Add tests to ensure that d_ino matches st_ino.

tests/c/testsuite/fdopendir-with-access.c

@@ -3,13 +3,15 @@
 #include <fcntl.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/stat.h>
 #include <unistd.h>
 
 int main(int argc, char *argv[]) {
   DIR *d;
   struct dirent *dp;
   int dfd;
   int expected[2] = {0};
+  ino_t inodes[2];
 
   dfd = open("fs-tests.dir/fopendir.dir", O_RDONLY | O_DIRECTORY);
   assert(dfd != -1);
@@ -23,16 +25,26 @@ int main(int argc, char *argv[]) {
     }
     if (strncmp(dp->d_name, "file-0", 6) == 0) {
       expected[0] = 1;
+      inodes[0] = dp->d_ino;
     } else if (strncmp(dp->d_name, "file-1", 6) == 0) {
       expected[1] = 1;
+      inodes[1] = dp->d_ino;
     } else {
       assert(0); // unexpected file
     }
+
+    // Ensure that `d_ino` matches what `fstatat`'s `st_ino` tells us.
+    struct stat statbuf;
+    if (fstatat(dfd, dp->d_name, &statbuf, AT_SYMLINK_NOFOLLOW) != 0) {
+      assert(0);
+    }
+    assert(statbuf.st_ino == dp->d_ino);
   }
   closedir(d);
 
   assert(expected[0] == 1);
   assert(expected[1] == 1);
+  assert(inodes[0] != inodes[1]);
 
   return EXIT_SUCCESS;
 }