The patch fixes build failure of form:
     ../src/alpha/osf.S:298:2: error: #error "osf.S out of sync with ffi.h"
Upstream fixed the bug in a more invasive way
but didn't have releases since 3.2.1.

The patch is taken from Gentoo:
https://gitweb.gentoo.org/repo/gentoo.git/tree/dev-libs/libffi/files/libffi-3.2.1-complex_alpha.patch

--- libffi-3.2.1/src/alpha/osf.S	2015-01-16 10:46:15.000000000 +0100
+++ libffi-3.2.1/src/alpha/osf.S	2015-01-16 10:46:24.000000000 +0100
@@ -279,6 +279,7 @@
 	.gprel32 $load_64	# FFI_TYPE_SINT64
 	.gprel32 $load_none	# FFI_TYPE_STRUCT
 	.gprel32 $load_64	# FFI_TYPE_POINTER
+	.gprel32 $load_none	# FFI_TYPE_COMPLEX
 
 /* Assert that the table above is in sync with ffi.h.  */
 
@@ -294,7 +295,8 @@
 	|| FFI_TYPE_SINT64 != 12	\
 	|| FFI_TYPE_STRUCT != 13	\
 	|| FFI_TYPE_POINTER != 14	\
-	|| FFI_TYPE_LAST != 14
+	|| FFI_TYPE_COMPLEX != 15       \
+	|| FFI_TYPE_LAST != 15
 #error "osf.S out of sync with ffi.h"
 #endif
 
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<div class='path'>path: <a href='/guix/log/?id=8afa00908b43d344d8c3fdd3c89d3dea4c205429'>root</a>/<a href='/guix/log/gnu?id=8afa00908b43d344d8c3fdd3c89d3dea4c205429'>gnu</a>/<a href='/guix/log/gnu/bootloader?id=8afa00908b43d344d8c3fdd3c89d3dea4c205429'>bootloader</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/bootloader?id=8afa00908b43d344d8c3fdd3c89d3dea4c205429&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-12-01 17:51:37 +0100'>2021-12-01</span></td><td><a href='/guix/commit/gnu/bootloader?id=adce91a3ec0cb2912daa6eefe9324c15ff3126f7'>gnu: system: Add LUKS2 support for the root file system.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/bootloader/grub.scm (grub-configuration-file): Add 'insmod
luks2'.
* gnu/system/mapped-devices.scm (open-luks-device): Create
'/run/cryptsetup/' directory.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Josselin Poiret</td></tr>
<tr><td><span title='2021-08-29 01:05:26 -0400'>2021-08-29</span></td><td><a href='/guix/commit/gnu/bootloader?id=da4e40948326387d5bcda58783914d5f9ce8b095'>Migrate to the new 'targets' field of bootloader-configuration.</a><span class='msg-avail'>...<span class='msg-tooltip'>The old 'target' field is deprecated; adjust the sources to use the new
'targets' one instead.

* doc/guix-cookbook.texi&lt;target&gt;: Replace by 'targets'.
* gnu/bootloader/grub.scm: Likewise.
* gnu/installer/parted.scm: Likewise.
* gnu/machine/digital-ocean.scm: Likewise.
* gnu/system/examples/asus-c201.tmpl: Likewise
* gnu/system/examples/bare-bones.tmpl: Likewise
* gnu/system/examples/bare-hurd.tmpl: Likewise
* gnu/system/examples/beaglebone-black.tmpl: Likewise
* gnu/system/examples/desktop.tmpl: Likewise
* gnu/system/examples/docker-image.tmpl: Likewise
* gnu/system/examples/lightweight-desktop.tmpl: Likewise
* gnu/system/examples/vm-image.tmpl: Likewise
* gnu/system/examples/yggdrasil.tmpl: Likewise
* gnu/system/hurd.scm: Likewise
* gnu/system/images/hurd.scm: Likewise
* gnu/system/images/novena.scm: Likewise
* gnu/system/images/pine64.scm: Likewise
* gnu/system/images/pinebook-pro.scm: Likewise
* gnu/system/images/rock64.scm: Likewise
* gnu/system/install.scm: Likewise
* gnu/system/vm.scm: Likewise
* gnu/tests.scm: Likewise
* gnu/tests/ganeti.scm: Likewise
* gnu/tests/install.scm: Likewise
* gnu/tests/nfs.scm: Likewise
* gnu/tests/telephony.scm: Likewise
* tests/boot-parameters.scm: Likewise
* tests/system.scm: Likewise
</span></span></td><td>Maxim Cournoyer</td></tr>