diff --git a/.gitignore b/.gitignore
index e69de29..29e2564 100644
--- a/.gitignore
+++ b/.gitignore
@@ -0,0 +1 @@
+/64tass-1.50.486.zip
diff --git a/64tass-1.50.486-ptrcast.patch b/64tass-1.50.486-ptrcast.patch
new file mode 100644
index 0000000..6295aaa
--- /dev/null
+++ b/64tass-1.50.486-ptrcast.patch
@@ -0,0 +1,12 @@
+diff -up 64tass-1.50.486/obj.c.ptrcast 64tass-1.50.486/obj.c
+--- 64tass-1.50.486/obj.c.ptrcast	2013-06-11 17:02:49.075972646 -0600
++++ 64tass-1.50.486/obj.c	2013-06-11 17:03:25.127641322 -0600
+@@ -129,7 +129,7 @@ static int invalid_hash(const struct val
+ }
+ 
+ static int gap_hash(const struct value_s *UNUSED(v1), struct value_s *UNUSED(v), linepos_t UNUSED(epoint)) {
+-    return (unsigned int)GAP_OBJ & ((~(unsigned int)0) >> 1);
++    return (intptr_t)GAP_OBJ & ((~(intptr_t)0) >> 1);
+ }
+ 
+ static void invalid_convert(struct value_s *v1, struct value_s *v, obj_t UNUSED(t), linepos_t epoint, linepos_t UNUSED(epoint2)) {
diff --git a/64tass-1.50.486-sizet.patch b/64tass-1.50.486-sizet.patch
new file mode 100644
index 0000000..e9f556d
--- /dev/null
+++ b/64tass-1.50.486-sizet.patch
@@ -0,0 +1,57 @@
+diff -up 64tass-1.50.486/misc.c.sizet 64tass-1.50.486/misc.c
+--- 64tass-1.50.486/misc.c.sizet	2013-06-11 17:00:35.876501904 -0600
++++ 64tass-1.50.486/misc.c	2013-06-11 17:02:16.489368315 -0600
+@@ -241,28 +241,28 @@ static void labelprint2(const struct avl
+                 case D_BYTE: 
+                     fputs(" byte", flab);
+                     if (l->value->u.code.size > 1) {
+-                        fprintf(flab, " %x", l->value->u.code.size);
++                        fprintf(flab, " %zx", l->value->u.code.size);
+                     }
+                     break;
+                 case D_INT:
+                 case D_WORD: 
+                     fputs(" word", flab);
+                     if (l->value->u.code.size > 2) {
+-                        fprintf(flab, " %x", l->value->u.code.size);
++                        fprintf(flab, " %zx", l->value->u.code.size);
+                     }
+                     break;
+                 case D_LINT:
+                 case D_LONG:
+                     fputs(" long", flab);
+                     if (l->value->u.code.size > 3) {
+-                        fprintf(flab, " %x", l->value->u.code.size);
++                        fprintf(flab, " %zx", l->value->u.code.size);
+                     }
+                     break;
+                 case D_DINT:
+                 case D_DWORD:
+                     fputs(" dword", flab);
+                     if (l->value->u.code.size > 4) {
+-                        fprintf(flab, " %x", l->value->u.code.size);
++                        fprintf(flab, " %zx", l->value->u.code.size);
+                     }
+                     break;
+                 case D_NONE:
+diff -up 64tass-1.50.486/section.c.sizet 64tass-1.50.486/section.c
+--- 64tass-1.50.486/section.c.sizet	2013-06-11 17:00:30.438400433 -0600
++++ 64tass-1.50.486/section.c	2013-06-11 17:01:27.084451753 -0600
+@@ -151,7 +151,7 @@ void sectionprint(void) {
+     l = &root_section;
+     if (l->size) {
+         sprintf(temp, "$%04" PRIaddress, l->start);
+-        sprintf(temp2, "$%04" PRIaddress, l->start + l->size - 1);
++        sprintf(temp2, "$%04zx", l->start + l->size - 1);
+         printf("Section:         %7s-%-7s\n", temp, temp2);
+     }
+     memprint(&l->mem);
+@@ -160,7 +160,7 @@ void sectionprint(void) {
+         if (l->defpass == pass) {
+             if (l->size) {
+                 sprintf(temp, "$%04" PRIaddress, l->start);
+-                sprintf(temp2, "$%04" PRIaddress, l->start + l->size - 1);
++                sprintf(temp2, "$%04zx", l->start + l->size - 1);
+                 printf("Section:         %7s-%-7s ", temp, temp2);
+             } else {
+                 printf("Section:                         ");
diff --git a/64tass.spec b/64tass.spec
new file mode 100644
index 0000000..edc2f61
--- /dev/null
+++ b/64tass.spec
@@ -0,0 +1,61 @@
+Name:		64tass
+Version:	1.50.486
+Release:	1%{?dist}
+Summary:	6502 assembler
+Group:		Development/Languages
+License:	GPLv2+
+URL:		http://tass64.sourceforge.net/
+BuildRequires:	w3m
+
+# The following would meet the Fedora Packaging Guidelines for Source URLs
+# for SourceForge, but it doesn't actually work! Despite the "/source/" in
+# the path, it actually gets the *binary* release ZIP archives.  This may have
+# something to do with the fact that the source and binary release ZIP
+# archives have the same name.  I've requested that upstream start putting
+# "-source" or "-src" in the names of the source archives, which hopefully
+# would fix this problem.
+#   https://sourceforge.net/p/tass64/bugs/13/
+#Source0:	http://downloads.sourceforge.net/tass64/source/%{name}-%{version}.zip
+
+Source0:	http://sourceforge.net/projects/tass64/files/source/%{name}-%{version}.zip
+
+# Fix problem with printf conversions of size_t. Reported upstream with
+# proposed patch:
+#   https://sourceforge.net/p/tass64/bugs/14/
+Patch0:		64tass-1.50.486-sizet.patch
+
+# Fix problem with cast of pointer to int. Reported upstream with
+# proposed patch:
+#   https://sourceforge.net/p/tass64/bugs/15/
+Patch1:		64tass-1.50.486-ptrcast.patch
+
+%description
+64tass is a multi-pass optimizing macro assembler for the 65xx series of
+processors. It supports the 6502, 65C02, R65C02, W65C02, 65CE02, 65816,
+DTV, and 65EL02, using a syntax similar to that of Omicron TASS and TASM.
+
+%prep
+%setup -q
+%patch -P 0 -p1 -b .sizet
+%patch -P 1 -p1 -b .ptrcast
+rm README  # will be built
+
+%build
+make %{?_smp_mflags} CFLAGS="%{optflags}"
+
+%install
+
+# install binaries
+install -d %{buildroot}%{_bindir}/
+install -m 755 64tass %{buildroot}%{_bindir}/
+
+%files
+%{_bindir}/64tass
+%doc README README.html
+%doc LICENSE-GPL-2.0
+%doc LICENSE-LGPL-2.0 LICENSE-LGPL-2.1
+%doc LICENSE-my_getopt
+
+%changelog
+* Tue Jun 11 2013 Eric Smith <brouhaha@fedoraproject.org> 1.50.486-1
+- Initial version
diff --git a/sources b/sources
index e69de29..337dfaf 100644
--- a/sources
+++ b/sources
@@ -0,0 +1 @@
+3f2e6a68123d0d8b786cc5f19d115003  64tass-1.50.486.zip