[PATCH] gdb: remove unnecessary NULL checks before xfree

Simon Marchi
2020-05-21T15:10:35Z

I was inspired by a series of patches merged by Alan Modra in the other
projects, so I did the same in GDB with a bit of Coccinelle and grep.

This patch removes the unnecessary NULL checks before calls to xfree.
They are unnecessary because xfree already does a NULL check. Since
free is supposed to handle NULL values correctly, the NULL check in
xfree itself is also questionable, but I've left it there for now.

gdb/ChangeLog:

* coffread.c (patch_type): Remove NULL check before xfree.
* corefile.c (set_gnutarget): Likewise.
* cp-abi.c (set_cp_abi_as_auto_default): Likewise.
* exec.c (build_section_table): Likewise.
* remote.c (remote_target::pass_signals): Likewise.
* utils.c (n_spaces): Likewise.
* cli/cli-script.c (document_command): Likewise.
* i386-windows-tdep.c (core_process_module_section): Likewise.
* linux-fork.c (struct fork_info) <~fork_info>: Likewise.
---
gdb/cli/cli-script.c | 3 +--
gdb/coffread.c | 3 +--
gdb/corefile.c | 3 +--
gdb/cp-abi.c | 6 ++----
gdb/exec.c | 3 +--
gdb/i386-windows-tdep.c | 3 +--
gdb/linux-fork.c | 4 ++--
gdb/remote.c | 3 +--
gdb/symfile.c | 3 +--
gdb/utils.c | 3 +--
10 files changed, 12 insertions(+), 22 deletions(-)

diff --git a/gdb/cli/cli-script.c b/gdb/cli/cli-script.c
index c9d23789068d..90ee67a5f3d3 100644
--- a/gdb/cli/cli-script.c
+++ b/gdb/cli/cli-script.c
@@ -1528,8 +1528,7 @@ document_command (const char *comname, int from_tty)
counted_command_line doclines = read_command_lines (prompt.c_str (),
from_tty, 0, 0);

- if (c->doc)
- xfree ((char *) c->doc);
+ xfree ((char *) c->doc);

{
struct command_line *cl1;
diff --git a/gdb/coffread.c b/gdb/coffread.c
index fc44e53cc4c4..0f7a6e3e5ad0 100644
--- a/gdb/coffread.c
+++ b/gdb/coffread.c
@@ -1467,8 +1467,7 @@ patch_type (struct type *type, struct type *real_type)
{
/* The previous copy of TYPE_NAME is allocated by
process_coff_symbol. */
- if (target->name ())
- xfree ((char*) target->name ());
+ xfree ((char *) target->name ());
target->set_name (xstrdup (real_target->name ()));
}
}
diff --git a/gdb/corefile.c b/gdb/corefile.c
index 4ce1bb78f282..996e5301b27a 100644
--- a/gdb/corefile.c
+++ b/gdb/corefile.c
@@ -472,8 +472,7 @@ complete_set_gnutarget (struct cmd_list_element *cmd,
void
set_gnutarget (const char *newtarget)
{
- if (gnutarget_string != NULL)
- xfree (gnutarget_string);
+ xfree (gnutarget_string);
gnutarget_string = xstrdup (newtarget);
set_gnutarget_command (NULL, 0, NULL);
}
diff --git a/gdb/cp-abi.c b/gdb/cp-abi.c
index 6997a7bdbe9b..3e2edad45ca3 100644
--- a/gdb/cp-abi.c
+++ b/gdb/cp-abi.c
@@ -273,10 +273,8 @@ set_cp_abi_as_auto_default (const char *short_name)
_("Cannot find C++ ABI \"%s\" to set it as auto default."),
short_name);

- if (auto_cp_abi.longname != NULL)
- xfree ((char *) auto_cp_abi.longname);
- if (auto_cp_abi.doc != NULL)
- xfree ((char *) auto_cp_abi.doc);
+ xfree ((char *) auto_cp_abi.longname);
+ xfree ((char *) auto_cp_abi.doc);

auto_cp_abi = *abi;

diff --git a/gdb/exec.c b/gdb/exec.c
index 93dd157e583e..14c77495a38f 100644
--- a/gdb/exec.c
+++ b/gdb/exec.c
@@ -648,8 +648,7 @@ build_section_table (struct bfd *some_bfd, struct target_section **start,
unsigned count;

count = bfd_count_sections (some_bfd);
- if (*start)
- xfree (* start);
+ xfree (*start);
*start = XNEWVEC (struct target_section, count);
*end = *start;
bfd_map_over_sections (some_bfd, add_to_section_table, (char *) end);
diff --git a/gdb/i386-windows-tdep.c b/gdb/i386-windows-tdep.c
index 7233b1f28f51..f5965399abce 100644
--- a/gdb/i386-windows-tdep.c
+++ b/gdb/i386-windows-tdep.c
@@ -142,8 +142,7 @@ core_process_module_section (bfd *abfd, asection *sect, void *obj)
data->module_count++;

out:
- if (buf)
- xfree (buf);
+ xfree (buf);
return;
}

diff --git a/gdb/linux-fork.c b/gdb/linux-fork.c
index 2233d4429ce0..e232d9c263a2 100644
--- a/gdb/linux-fork.c
+++ b/gdb/linux-fork.c
@@ -61,8 +61,8 @@ struct fork_info

if (savedregs)
delete savedregs;
- if (filepos)
- xfree (filepos);
+
+ xfree (filepos);
}

ptid_t ptid = null_ptid;
diff --git a/gdb/remote.c b/gdb/remote.c
index 312a03c8fb42..c73eb6e9e136 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -2615,8 +2615,7 @@ remote_target::pass_signals (gdb::array_view<const unsigned char> pass_signals)
putpkt (pass_packet);
getpkt (&rs->buf, 0);
packet_ok (rs->buf, &remote_protocol_packets[PACKET_QPassSignals]);
- if (rs->last_pass_packet)
- xfree (rs->last_pass_packet);
+ xfree (rs->last_pass_packet);
rs->last_pass_packet = pass_packet;
}
else
diff --git a/gdb/symfile.c b/gdb/symfile.c
index b02a9235663b..b29f864b3735 100644
--- a/gdb/symfile.c
+++ b/gdb/symfile.c
@@ -3404,8 +3404,7 @@ enum ovly_index
static void
simple_free_overlay_table (void)
{
- if (cache_ovly_table)
- xfree (cache_ovly_table);
+ xfree (cache_ovly_table);
cache_novlys = 0;
cache_ovly_table = NULL;
cache_ovly_table_base = 0;
diff --git a/gdb/utils.c b/gdb/utils.c
index 989b13d0e0f3..d2290c30a78b 100644
--- a/gdb/utils.c
+++ b/gdb/utils.c
@@ -2260,8 +2260,7 @@ n_spaces (int n)

if (n > max_spaces)
{
- if (spaces)
- xfree (spaces);
+ xfree (spaces);
spaces = (char *) xmalloc (n + 1);
for (t = spaces + n; t != spaces;)
*--t = ' ';
--
2.26.2