diff --git a/tcsh-6.19.00-025-more-generous-ROUNDUP-_LP64.patch b/tcsh-6.19.00-025-more-generous-ROUNDUP-_LP64.patch
new file mode 100644
index 0000000..73daef4
--- /dev/null
+++ b/tcsh-6.19.00-025-more-generous-ROUNDUP-_LP64.patch
@@ -0,0 +1,28 @@
+From f71cda754740dbf7a2d6aee848a93a8239ba4480 Mon Sep 17 00:00:00 2001
+From: christos <christos>
+Date: Tue, 8 Mar 2016 12:47:43 +0000
+Subject: [PATCH] More generous ROUNDUP for _LP64
+
+---
+ tc.alloc.c | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+diff --git a/tc.alloc.c b/tc.alloc.c
+index f68a8c5..86aae80 100644
+--- a/tc.alloc.c
++++ b/tc.alloc.c
+@@ -134,7 +134,11 @@ union overhead {
+ #endif
+ 
+ 
++#ifdef _LP64
++#define ROUNDUP	15
++#else
+ #define ROUNDUP	7
++#endif
+ 
+ /*
+  * nextf[i] is the pointer to the next free block of size 2^(i+3).  The
+-- 
+2.5.5
+
diff --git a/tcsh.spec b/tcsh.spec
index 28be5e0..b2b6895 100644
--- a/tcsh.spec
+++ b/tcsh.spec
@@ -53,6 +53,7 @@ Patch021: tcsh-6.19.00-021-remove-extra-semicolon.patch
 Patch022: tcsh-6.19.00-022-fix-source-command-memory-leak.patch
 Patch023: tcsh-6.19.00-023-fix-debugging-code.patch
 Patch024: tcsh-6.19.00-024-use-sysmalloc.patch
+Patch025: tcsh-6.19.00-025-more-generous-ROUNDUP-_LP64.patch
 
 
 # Downstream patches -- these should be always included when doing rebase:
@@ -198,6 +199,7 @@ fi
     tcsh-6.19.00-022-fix-source-command-memory-leak.patch
     tcsh-6.19.00-023-fix-debugging-code.patch
     tcsh-6.19.00-024-use-sysmalloc.patch
+    tcsh-6.19.00-025-more-generous-ROUNDUP-_LP64.patch
 
 * Thu Apr 21 2016 David Kaspar [Dee'Kej] <dkaspar@redhat.com> - 6.19.00-6
 - Drop tcsh-6.15.00-closem.patch - issue not reproducible, patch not accepted by upstream