[glibc/maskray/relr] stdlib: Fix tst-canon-bz26341 when the glibc build current working directory is itself using symlink

[glibc/maskray/relr] stdlib: Fix tst-canon-bz26341 when the glibc build current working directory is itself using symlink

[Fangrui Song]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=e037274c8ec86ca9d491331984b34f30701b23cf

commit e037274c8ec86ca9d491331984b34f30701b23cf
Author: omain GEISSLER <romain.geissler@amadeus.com>
Date:   Wed Oct 20 12:01:40 2021 -0300

    stdlib: Fix tst-canon-bz26341 when the glibc build current working directory is itself using symlinks.

Diff:
---
 stdlib/tst-canon-bz26341.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/stdlib/tst-canon-bz26341.c b/stdlib/tst-canon-bz26341.c
index acb0fd4ec3..fddf4adff3 100644
--- a/stdlib/tst-canon-bz26341.c
+++ b/stdlib/tst-canon-bz26341.c
@@ -45,6 +45,12 @@ create_link (void)
   TEST_VERIFY_EXIT (fd != -1);
   xclose (fd);
 
+  /* Make filename a canonical path.  */
+  char *saved_filename = filename;
+  filename = realpath (filename, NULL);
+  free (saved_filename);
+  TEST_VERIFY (filename != NULL);
+
   /* Create MAXLINKS symbolic links to the temporary filename.
      On exit, linkname has the last link created.  */
   char *prevlink = filename;