From: Tom Tromey <tom@tromey.com>
Date: Fri, 20 Jul 2018 03:10:09 +0000 (-0600)
Subject: Fix crash with -D_GLIBCXX_DEBUG
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=463c08d160e55d6eaf0f9bc3729781ce90f4de3f;p=binutils-gdb.git

Fix crash with -D_GLIBCXX_DEBUG

I noticed a buildbot failure where gdb crashed in info-os.exp, when
compiled with -D_GLIBCXX_DEBUG:

    (gdb) info os procgroups
    /usr/include/c++/7/bits/stl_algo.h:4834:
    Error: comparison doesn't meet irreflexive requirements, assert(!(a < a)).
    Objects involved in the operation:
	iterator::value_type "< operator type" {
	  type = pid_pgid_entry;
	}

The bug here is that pid_pgid_entry::operator< violates the C++
irreflexivity rule; that is, that an object cannot be less than
itself.

Tested locally by re-running info-os.exp.

gdb/ChangeLog
2018-07-30  Tom Tromey  <tom@tromey.com>

	* nat/linux-osdata.c (pid_pgid_entry::operator<): Fix
	irreflexivity violation.
---

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 2cd7d6498b0..24ffeecda11 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2018-07-30  Tom Tromey  <tom@tromey.com>
+
+	* nat/linux-osdata.c (pid_pgid_entry::operator<): Fix
+	irreflexivity violation.
+
 2018-07-30  Tom Tromey  <tom@tromey.com>
 
 	* cli/cli-decode.c (lookup_cmd): Remove lint code.
diff --git a/gdb/nat/linux-osdata.c b/gdb/nat/linux-osdata.c
index 25e895df190..2323dcc878b 100644
--- a/gdb/nat/linux-osdata.c
+++ b/gdb/nat/linux-osdata.c
@@ -415,9 +415,11 @@ struct pid_pgid_entry
 
     /* Process group leaders always come first...  */
     if (this->is_leader ())
-      return true;
-
-    if (other.is_leader ())
+      {
+	if (!other.is_leader ())
+	  return true;
+      }
+    else if (other.is_leader ())
       return false;
 
     /* ...else sort by PID.  */