[binutils-gdb] Fix leak due to assigning a xstrdup-ed string to the std::string gdb_datadir

[binutils-gdb] Fix leak due to assigning a xstrdup-ed string to the std::string gdb_datadir

[Philippe Waroquiers]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=cd7c32c36ae53c00e9b0731c58de37dc28b88fb6

commit cd7c32c36ae53c00e9b0731c58de37dc28b88fb6
Author: Philippe Waroquiers <philippe.waroquiers@skynet.be>
Date:   Sun Sep 29 18:26:23 2019 +0200

    Fix leak due to assigning a xstrdup-ed string to the std::string gdb_datadir
    
    Valgrind reports the following leak:
    ==32623== 56 bytes in 1 blocks are definitely lost in loss record 1,099 of 6,654
    ==32623==    at 0x4835753: malloc (vg_replace_malloc.c:307)
    ==32623==    by 0x25CF67: xmalloc (alloc.c:60)
    ==32623==    by 0x65FBD9: xstrdup (xstrdup.c:34)
    ==32623==    by 0x413D9E: captured_main_1(captured_main_args*) (main.c:553)
    ==32623==    by 0x414FFA: captured_main (main.c:1172)
    ==32623==    by 0x414FFA: gdb_main(captured_main_args*) (main.c:1197)
    ==32623==    by 0x22531A: main (gdb.c:32)
    
    Commit f2aec7f6d14 changed gdb_datadir to std::string.
    So, xstrdup-ing the result of relocate_gdb_directory (returning a std::string)
    is not needed and creates a leak.
    
    Fix the leak by removing the xstrdup and the not needed c_str ().
    Also removes a useless conversion of gdb_datadir to std::string.
    
    gdb/ChangeLog
    2019-10-01  Philippe Waroquiers  <philippe.waroquiers@skynet.be>
    
    	* main.c (relocate_gdbinit_path_maybe_in_datadir): Remove std::string
    	conversion of gdb_datadir.
    	(captured_main_1): Remove xstrdup when assigning to gdb_datadir,
    	remove not needed c_str ().

Diff:
---
 gdb/ChangeLog | 7 +++++++
 gdb/main.c    | 8 +++-----
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 1be7f4b..7285515 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,10 @@
+2019-10-01  Philippe Waroquiers  <philippe.waroquiers@skynet.be>
+
+	* main.c (relocate_gdbinit_path_maybe_in_datadir): Remove std::string
+	conversion of gdb_datadir.
+	(captured_main_1): Remove xstrdup when assigning to gdb_datadir,
+	remove not needed c_str ().
+
 2019-09-30  Ali Tamur <tamur@google.com>
 
 	* dwarf2read.c (skip_one_die): Handle DW_FORM_strx forms.
diff --git a/gdb/main.c b/gdb/main.c
index 7fab8ff..14d9e79 100644
--- a/gdb/main.c
+++ b/gdb/main.c
@@ -214,8 +214,7 @@ relocate_gdbinit_path_maybe_in_datadir (const std::string& file)
       size_t start = datadir_len;
       for (; IS_DIR_SEPARATOR (file[start]); ++start)
 	;
-      relocated_path = (std::string (gdb_datadir) + SLASH_STRING
-			+ file.substr (start));
+      relocated_path = gdb_datadir + SLASH_STRING + file.substr (start);
     }
   else
     {
@@ -549,9 +548,8 @@ captured_main_1 (struct captured_main_args *context)
     = xstrdup (relocate_gdb_directory (DEBUGDIR,
 				     DEBUGDIR_RELOCATABLE).c_str ());
 
-  gdb_datadir
-    = xstrdup (relocate_gdb_directory (GDB_DATADIR,
-				     GDB_DATADIR_RELOCATABLE).c_str ());
+  gdb_datadir = relocate_gdb_directory (GDB_DATADIR,
+					GDB_DATADIR_RELOCATABLE);
 
 #ifdef WITH_PYTHON_PATH
   {