[PATCH] gdb/compile: Use std::filesystem::remove_all in cleanup

[Lancelot SIX <lancelot.six@amd.com>]

In a previous review, I noticed that some code in gdb/compile/compile.c
could use c++17's `std::filesystem::remove_all` instead of using some
`system ("rm -rf ...");`.

This patch implements this.

Note that I use the noexcept overload of std::filesystem::remove_all and
explicitly check for an error code.  This means that this code called
during the cleanup procedure cannot throw, and does not risk preventing
other cleanup functions to be called.

Tested on x86_64-linux.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31420
Change-Id: If5668bf3e15e66c020e5c3b4fa999f861690e4cf
---
 gdb/compile/compile.c | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/gdb/compile/compile.c b/gdb/compile/compile.c
index 27cff2553ee..45452f19abb 100644
--- a/gdb/compile/compile.c
+++ b/gdb/compile/compile.c
@@ -40,7 +40,9 @@
 #include "osabi.h"
 #include "gdbsupport/gdb_wait.h"
 #include "valprint.h"
+#include <filesystem>
 #include <optional>
+#include <system_error>
 #include "gdbsupport/gdb_unlinker.h"
 #include "gdbsupport/pathstuff.h"
 #include "gdbsupport/scoped_ignore_signal.h"
@@ -450,15 +452,11 @@ get_compile_file_tempdir (void)
   tempdir_name = xstrdup (tempdir_name);
   add_final_cleanup ([] ()
     {
-      char *zap;
-      int wstat;
-
-      gdb_assert (startswith (tempdir_name, TMP_PREFIX));
-      zap = concat ("rm -rf ", tempdir_name, (char *) NULL);
-      wstat = system (zap);
-      if (wstat == -1 || !WIFEXITED (wstat) || WEXITSTATUS (wstat) != 0)
-	warning (_("Could not remove temporary directory %s"), tempdir_name);
-      XDELETEVEC (zap);
+      std::error_code error;
+      if (std::filesystem::remove_all (tempdir_name, error)
+	  == static_cast<std::uintmax_t> (-1))
+	warning (_("Could not remove temporary directory %s (%s)"),
+		 tempdir_name, error.message ().c_str ());
     });
   return tempdir_name;
 }

base-commit: 90f8d97c8efa75f7f019b868eca9c626bc35203d
-- 
2.34.1