libiberty: sync with gcc

Import the following commits from GCC as of r16-6728-g7c3584be8c8806:
	07df546fb90 libiberty/testsuite: make test-pexecute's -t option a little more useful
	0c775dcf3e7 libiberty: Make `objalloc_free' `free'-like WRT null pointer

libiberty/ChangeLog

diff --git a/libiberty/ChangeLog b/libiberty/ChangeLog
index 37c351d..95dce96 100644
--- a/libiberty/ChangeLog
+++ b/libiberty/ChangeLog
@@ -1,3 +1,12 @@
+2026-01-12  Maciej W. Rozycki  <macro@redhat.com>
+
+	* objalloc.c (objalloc_free): Don't use the pointer passed if
+	null.
+
+2026-01-09  Jan Beulich  <jbeulich@suse.com>
+
+	* testsuite/test-pexecute.c (main): Adjust a tracing fprintf().
+
 2025-11-30  Jose E. Marchesi  <jose.marchesi@oracle.com>
 
 	* simple-object-mach-o.c

libiberty/objalloc.c

diff --git a/libiberty/objalloc.c b/libiberty/objalloc.c
index 263d4b6..b3b255a 100644
--- a/libiberty/objalloc.c
+++ b/libiberty/objalloc.c
@@ -178,6 +178,10 @@
 {
   struct objalloc_chunk *l;
 
+  /* Handle a nullptr as being a no-op. */
+  if (o == NULL)
+    return;
+
   l = (struct objalloc_chunk *) o->chunks;
   while (l != NULL)
     {

libiberty/testsuite/test-pexecute.c

diff --git a/libiberty/testsuite/test-pexecute.c b/libiberty/testsuite/test-pexecute.c
index 3aaf268..b0e2c99 100644
--- a/libiberty/testsuite/test-pexecute.c
+++ b/libiberty/testsuite/test-pexecute.c
@@ -211,7 +211,7 @@
       const char *pex_run_err;						\
       if (trace)							\
 	fprintf (stderr, "Line %d: running %s %s\n",			\
-		 __LINE__, EXECUTABLE, ARGV[0]);			\
+		 __LINE__, EXECUTABLE, ARGV[1]);			\
       pex_run_err = pex_run (PEXOBJ, FLAGS, EXECUTABLE, ARGV, OUTNAME,	\
 			     ERRNAME, &err);				\
       if (pex_run_err != NULL)						\