Re: [PATCH 3/3] gdb: make macro_stringify return a gdb::unique_xmalloc_ptr<char>

[Simon Marchi <simon.marchi@polymtl.ca>]

On 2020-06-30 4:55 p.m., Tom Tromey wrote:
>>>>>> "Simon" == Simon Marchi via Gdb-patches <gdb-patches@sourceware.org> writes:
> 
> Simon> The change to macro_stringify is straightforward.  This allows removing
> Simon> the manual memory management in fixup_definition.
> 
> Simon> @@ -882,25 +882,19 @@ macro_undef (struct macro_source_file *source, int line,
> Simon>  static struct macro_definition *
> Simon>  fixup_definition (const char *filename, int line, struct macro_definition *def)
> Simon>  {
> Simon> -  static char *saved_expansion;
> [...]
> Simon> +  gdb::unique_xmalloc_ptr<char> saved_expansion;
>  
> This loses the "static", but that's necessary because this function
> returns "def", which has a pointer to the contents.

Oh damn, I fixed it last minute (it fails some tests) but probably forgot to git-add.

Here's the fixed version:


From e0ce95d17288009301534846fcb8c278f5d58fd7 Mon Sep 17 00:00:00 2001
From: Simon Marchi <simon.marchi@polymtl.ca>
Date: Sat, 27 Jun 2020 16:12:20 -0400
Subject: [PATCH] gdb: make macro_stringify return a gdb::unique_xmalloc_ptr<char>

The change to macro_stringify is straightforward.  This allows removing
the manual memory management in fixup_definition.

gdb/ChangeLog:

	* macroexp.h (macro_stringify): Return
	gdb::unique_xmalloc_ptr<char>.
	* macroexp.c (macro_stringify): Likewise.
	* macrotab.c (fixup_definition): Update.

Change-Id: Id7db8988bdbd569dd51c4f4655b00eb26db277cb
---

diff --git a/gdb/macroexp.c b/gdb/macroexp.c
index e1d185d..5f749ff 100644
--- a/gdb/macroexp.c
+++ b/gdb/macroexp.c
@@ -698,7 +698,7 @@

 /* See macroexp.h.  */

-char *
+gdb::unique_xmalloc_ptr<char>
 macro_stringify (const char *str)
 {
   int len = strlen (str);
@@ -707,7 +707,7 @@
   stringify (&buffer, str, len);
   buffer.appendc ('\0');

-  return buffer.release ().release ();
+  return buffer.release ();
 }

 \f
diff --git a/gdb/macroexp.h b/gdb/macroexp.h
index 511991c..2e29d02 100644
--- a/gdb/macroexp.h
+++ b/gdb/macroexp.h
@@ -78,9 +78,7 @@
 int macro_is_digit (int c);


-/* Stringify STR according to C rules and return an xmalloc'd pointer
-   to the result.  */
-
-char *macro_stringify (const char *str);
+/* Stringify STR according to C rules and return a null-terminated string.  */
+gdb::unique_xmalloc_ptr<char> macro_stringify (const char *str);

 #endif /* MACROEXP_H */
diff --git a/gdb/macrotab.c b/gdb/macrotab.c
index 63cd301..9ada436 100644
--- a/gdb/macrotab.c
+++ b/gdb/macrotab.c
@@ -882,25 +882,19 @@
 static struct macro_definition *
 fixup_definition (const char *filename, int line, struct macro_definition *def)
 {
-  static char *saved_expansion;
-
-  if (saved_expansion)
-    {
-      xfree (saved_expansion);
-      saved_expansion = NULL;
-    }
+  static gdb::unique_xmalloc_ptr<char> saved_expansion;

   if (def->kind == macro_object_like)
     {
       if (def->argc == macro_FILE)
 	{
 	  saved_expansion = macro_stringify (filename);
-	  def->replacement = saved_expansion;
+	  def->replacement = saved_expansion.get ();
 	}
       else if (def->argc == macro_LINE)
 	{
-	  saved_expansion = xstrprintf ("%d", line);
-	  def->replacement = saved_expansion;
+	  saved_expansion.reset (xstrprintf ("%d", line));
+	  def->replacement = saved_expansion.get ();
 	}
     }