[PATCH] Makefile: describe XMALLOC_POISON

[Alexander Kuleshov <kuleshovmail@gmail.com>]

The do_xmalloc() functions may fill an allocated buffer with the
known value (0xA5) for debugging if we will pass the XMALLOC_POISON
option during build.

This patch adds description of this option to the Makefile and
adds it to BASIC_CFLAGS if it was provided.

Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
---
 Makefile | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Makefile b/Makefile
index f3325de..3f942b5 100644
--- a/Makefile
+++ b/Makefile
@@ -367,6 +367,10 @@ all::
 # Define HAVE_BSD_SYSCTL if your platform has a BSD-compatible sysctl function.
 #
 # Define HAVE_GETDELIM if your system has the getdelim() function.
+#
+# Define XMALLOC_POISON if you are debugging the xmalloc(). In a XMALLOC_POISON
+# build, each allocated buffer by the xmalloc() will be in known state. After
+# memory allocation, a buffer will be filled with '0xA5' values.
 
 GIT-VERSION-FILE: FORCE
 	@$(SHELL_PATH) ./GIT-VERSION-GEN
@@ -1481,6 +1485,10 @@ ifdef HAVE_GETDELIM
 	BASIC_CFLAGS += -DHAVE_GETDELIM
 endif
 
+ifdef XMALLOC_POISON
+	BASIC_CFLAGS += -DXMALLOC_POISON
+endif
+
 ifeq ($(TCLTK_PATH),)
 NO_TCLTK = NoThanks
 endif
-- 
2.7.0.25.gfc10eb5