diff --git a/contrib/guix/manifest.scm b/contrib/guix/manifest.scm
index 3134e1db08..7c065b5183 100644
--- a/contrib/guix/manifest.scm
+++ b/contrib/guix/manifest.scm
@@ -167,13 +167,17 @@ desirable for building Dash Core release binaries."
 (define (make-gcc-with-pthreads gcc)
   (package-with-extra-configure-variable gcc "--enable-threads" "posix"))
 
+(define (make-mingw-w64-cross-gcc-vmov-alignment cross-gcc)
+  (package-with-extra-patches cross-gcc
+    (search-our-patches "vmov-alignment.patch")))
+
 (define (make-mingw-pthreads-cross-toolchain target)
   "Create a cross-compilation toolchain package for TARGET"
   (let* ((xbinutils (cross-binutils target))
          (pthreads-xlibc mingw-w64-x86_64-winpthreads)
          (pthreads-xgcc (make-gcc-with-pthreads
                          (cross-gcc target
-                                    #:xgcc (make-ssp-fixed-gcc base-gcc)
+                                    #:xgcc (make-ssp-fixed-gcc (make-mingw-w64-cross-gcc-vmov-alignment base-gcc))
                                     #:xbinutils xbinutils
                                     #:libc pthreads-xlibc))))
     ;; Define a meta-package that propagates the resulting XBINUTILS, XLIBC, and
diff --git a/contrib/guix/patches/vmov-alignment.patch b/contrib/guix/patches/vmov-alignment.patch
new file mode 100644
index 0000000000..072f76eafd
--- /dev/null
+++ b/contrib/guix/patches/vmov-alignment.patch
@@ -0,0 +1,267 @@
+Description: Use unaligned VMOV instructions
+Author: Stephen Kitt <skitt@debian.org>
+Bug-Debian: https://bugs.debian.org/939559
+
+Based on a patch originally by Claude Heiland-Allen <claude@mathr.co.uk>
+
+--- a/gcc/config/i386/sse.md
++++ b/gcc/config/i386/sse.md
+@@ -1058,17 +1058,11 @@
+ {
+   if (FLOAT_MODE_P (GET_MODE_INNER (<MODE>mode)))
+     {
+-      if (misaligned_operand (operands[1], <MODE>mode))
+-	return "vmovu<ssemodesuffix>\t{%1, %0%{%3%}%N2|%0%{%3%}%N2, %1}";
+-      else
+-	return "vmova<ssemodesuffix>\t{%1, %0%{%3%}%N2|%0%{%3%}%N2, %1}";
++      return "vmovu<ssemodesuffix>\t{%1, %0%{%3%}%N2|%0%{%3%}%N2, %1}";
+     }
+   else
+     {
+-      if (misaligned_operand (operands[1], <MODE>mode))
+-	return "vmovdqu<ssescalarsize>\t{%1, %0%{%3%}%N2|%0%{%3%}%N2, %1}";
+-      else
+-	return "vmovdqa<ssescalarsize>\t{%1, %0%{%3%}%N2|%0%{%3%}%N2, %1}";
++      return "vmovdqu<ssescalarsize>\t{%1, %0%{%3%}%N2|%0%{%3%}%N2, %1}";
+     }
+ }
+   [(set_attr "type" "ssemov")
+@@ -1184,17 +1178,11 @@
+ {
+   if (FLOAT_MODE_P (GET_MODE_INNER (<MODE>mode)))
+     {
+-      if (misaligned_operand (operands[0], <MODE>mode))
+-	return "vmovu<ssemodesuffix>\t{%1, %0%{%2%}|%0%{%2%}, %1}";
+-      else
+-	return "vmova<ssemodesuffix>\t{%1, %0%{%2%}|%0%{%2%}, %1}";
++      return "vmovu<ssemodesuffix>\t{%1, %0%{%2%}|%0%{%2%}, %1}";
+     }
+   else
+     {
+-      if (misaligned_operand (operands[0], <MODE>mode))
+-	return "vmovdqu<ssescalarsize>\t{%1, %0%{%2%}|%0%{%2%}, %1}";
+-      else
+-	return "vmovdqa<ssescalarsize>\t{%1, %0%{%2%}|%0%{%2%}, %1}";
++      return "vmovdqu<ssescalarsize>\t{%1, %0%{%2%}|%0%{%2%}, %1}";
+     }
+ }
+   [(set_attr "type" "ssemov")
+@@ -7806,7 +7794,7 @@
+   "TARGET_SSE && !(MEM_P (operands[0]) && MEM_P (operands[1]))"
+   "@
+    %vmovlps\t{%1, %0|%q0, %1}
+-   %vmovaps\t{%1, %0|%0, %1}
++   %vmovups\t{%1, %0|%0, %1}
+    %vmovlps\t{%1, %d0|%d0, %q1}"
+   [(set_attr "type" "ssemov")
+    (set_attr "prefix" "maybe_vex")
+@@ -13997,29 +13985,15 @@
+   switch (<MODE>mode)
+     {
+     case E_V8DFmode:
+-      if (misaligned_operand (operands[2], <ssequartermode>mode))
+-	return "vmovupd\t{%2, %x0|%x0, %2}";
+-      else
+-	return "vmovapd\t{%2, %x0|%x0, %2}";
++      return "vmovupd\t{%2, %x0|%x0, %2}";
+     case E_V16SFmode:
+-      if (misaligned_operand (operands[2], <ssequartermode>mode))
+-	return "vmovups\t{%2, %x0|%x0, %2}";
+-      else
+-	return "vmovaps\t{%2, %x0|%x0, %2}";
++      return "vmovups\t{%2, %x0|%x0, %2}";
+     case E_V8DImode:
+-      if (misaligned_operand (operands[2], <ssequartermode>mode))
+-	return which_alternative == 2 ? "vmovdqu64\t{%2, %x0|%x0, %2}"
++      return which_alternative == 2 ? "vmovdqu64\t{%2, %x0|%x0, %2}"
+ 				      : "vmovdqu\t{%2, %x0|%x0, %2}";
+-      else
+-	return which_alternative == 2 ? "vmovdqa64\t{%2, %x0|%x0, %2}"
+-				      : "vmovdqa\t{%2, %x0|%x0, %2}";
+     case E_V16SImode:
+-      if (misaligned_operand (operands[2], <ssequartermode>mode))
+-	return which_alternative == 2 ? "vmovdqu32\t{%2, %x0|%x0, %2}"
++      return which_alternative == 2 ? "vmovdqu32\t{%2, %x0|%x0, %2}"
+ 				      : "vmovdqu\t{%2, %x0|%x0, %2}";
+-      else
+-	return which_alternative == 2 ? "vmovdqa32\t{%2, %x0|%x0, %2}"
+-				      : "vmovdqa\t{%2, %x0|%x0, %2}";
+     default:
+       gcc_unreachable ();
+     }
+@@ -21225,63 +21199,27 @@
+       switch (get_attr_mode (insn))
+ 	{
+ 	case MODE_V16SF:
+-	  if (misaligned_operand (operands[1], <ssehalfvecmode>mode))
+-	    return "vmovups\t{%1, %t0|%t0, %1}";
+-	  else
+-	    return "vmovaps\t{%1, %t0|%t0, %1}";
++	  return "vmovups\t{%1, %t0|%t0, %1}";
+ 	case MODE_V8DF:
+-	  if (misaligned_operand (operands[1], <ssehalfvecmode>mode))
+-	    return "vmovupd\t{%1, %t0|%t0, %1}";
+-	  else
+-	    return "vmovapd\t{%1, %t0|%t0, %1}";
++	  return "vmovupd\t{%1, %t0|%t0, %1}";
+ 	case MODE_V8SF:
+-	  if (misaligned_operand (operands[1], <ssehalfvecmode>mode))
+-	    return "vmovups\t{%1, %x0|%x0, %1}";
+-	  else
+-	    return "vmovaps\t{%1, %x0|%x0, %1}";
++	  return "vmovups\t{%1, %x0|%x0, %1}";
+ 	case MODE_V4DF:
+-	  if (misaligned_operand (operands[1], <ssehalfvecmode>mode))
+-	    return "vmovupd\t{%1, %x0|%x0, %1}";
+-	  else
+-	    return "vmovapd\t{%1, %x0|%x0, %1}";
++	  return "vmovupd\t{%1, %x0|%x0, %1}";
+ 	case MODE_XI:
+-	  if (misaligned_operand (operands[1], <ssehalfvecmode>mode))
+-	    {
+-	      if (which_alternative == 2)
+-		return "vmovdqu\t{%1, %t0|%t0, %1}";
+-	      else if (GET_MODE_SIZE (<ssescalarmode>mode) == 8)
+-		return "vmovdqu64\t{%1, %t0|%t0, %1}";
+-	      else
+-		return "vmovdqu32\t{%1, %t0|%t0, %1}";
+-	    }
++	  if (which_alternative == 2)
++	    return "vmovdqu\t{%1, %t0|%t0, %1}";
++	  else if (GET_MODE_SIZE (<ssescalarmode>mode) == 8)
++	    return "vmovdqu64\t{%1, %t0|%t0, %1}";
+ 	  else
+-	    {
+-	      if (which_alternative == 2)
+-		return "vmovdqa\t{%1, %t0|%t0, %1}";
+-	      else if (GET_MODE_SIZE (<ssescalarmode>mode) == 8)
+-		return "vmovdqa64\t{%1, %t0|%t0, %1}";
+-	      else
+-		return "vmovdqa32\t{%1, %t0|%t0, %1}";
+-	    }
++	    return "vmovdqu32\t{%1, %t0|%t0, %1}";
+ 	case MODE_OI:
+-	  if (misaligned_operand (operands[1], <ssehalfvecmode>mode))
+-	    {
+-	      if (which_alternative == 2)
+-		return "vmovdqu\t{%1, %x0|%x0, %1}";
+-	      else if (GET_MODE_SIZE (<ssescalarmode>mode) == 8)
+-		return "vmovdqu64\t{%1, %x0|%x0, %1}";
+-	      else
+-		return "vmovdqu32\t{%1, %x0|%x0, %1}";
+-	    }
++	  if (which_alternative == 2)
++	    return "vmovdqu\t{%1, %x0|%x0, %1}";
++	  else if (GET_MODE_SIZE (<ssescalarmode>mode) == 8)
++	    return "vmovdqu64\t{%1, %x0|%x0, %1}";
+ 	  else
+-	    {
+-	      if (which_alternative == 2)
+-		return "vmovdqa\t{%1, %x0|%x0, %1}";
+-	      else if (GET_MODE_SIZE (<ssescalarmode>mode) == 8)
+-		return "vmovdqa64\t{%1, %x0|%x0, %1}";
+-	      else
+-		return "vmovdqa32\t{%1, %x0|%x0, %1}";
+-	    }
++	    return "vmovdqu32\t{%1, %x0|%x0, %1}";
+ 	default:
+ 	  gcc_unreachable ();
+ 	}
+--- a/gcc/config/i386/i386.c
++++ b/gcc/config/i386/i386.c
+@@ -4981,13 +4981,13 @@
+       switch (type)
+ 	{
+ 	case opcode_int:
+-	  opcode = misaligned_p ? "vmovdqu32" : "vmovdqa32";
++	  opcode = "vmovdqu32";
+ 	  break;
+ 	case opcode_float:
+-	  opcode = misaligned_p ? "vmovups" : "vmovaps";
++	  opcode = "vmovups";
+ 	  break;
+ 	case opcode_double:
+-	  opcode = misaligned_p ? "vmovupd" : "vmovapd";
++	  opcode = "vmovupd";
+ 	  break;
+ 	}
+     }
+@@ -4996,16 +4996,16 @@
+       switch (scalar_mode)
+ 	{
+ 	case E_SFmode:
+-	  opcode = misaligned_p ? "%vmovups" : "%vmovaps";
++	  opcode = "%vmovups";
+ 	  break;
+ 	case E_DFmode:
+-	  opcode = misaligned_p ? "%vmovupd" : "%vmovapd";
++	  opcode = "%vmovupd";
+ 	  break;
+ 	case E_TFmode:
+ 	  if (evex_reg_p)
+-	    opcode = misaligned_p ? "vmovdqu64" : "vmovdqa64";
++	    opcode = "vmovdqu64";
+ 	  else
+-	    opcode = misaligned_p ? "%vmovdqu" : "%vmovdqa";
++	    opcode = "%vmovdqu";
+ 	  break;
+ 	default:
+ 	  gcc_unreachable ();
+@@ -5017,48 +5017,32 @@
+ 	{
+ 	case E_QImode:
+ 	  if (evex_reg_p)
+-	    opcode = (misaligned_p
+-		      ? (TARGET_AVX512BW
+-			 ? "vmovdqu8"
+-			 : "vmovdqu64")
+-		      : "vmovdqa64");
++	    opcode = TARGET_AVX512BW ? "vmovdqu8" : "vmovdqu64";
+ 	  else
+-	    opcode = (misaligned_p
+-		      ? (TARGET_AVX512BW
+-			 ? "vmovdqu8"
+-			 : "%vmovdqu")
+-		      : "%vmovdqa");
++	    opcode = TARGET_AVX512BW ? "vmovdqu8" : "%vmovdqu";
+ 	  break;
+ 	case E_HImode:
+ 	  if (evex_reg_p)
+-	    opcode = (misaligned_p
+-		      ? (TARGET_AVX512BW
+-			 ? "vmovdqu16"
+-			 : "vmovdqu64")
+-		      : "vmovdqa64");
++	    opcode = TARGET_AVX512BW ? "vmovdqu16" : "vmovdqu64";
+ 	  else
+-	    opcode = (misaligned_p
+-		      ? (TARGET_AVX512BW
+-			 ? "vmovdqu16"
+-			 : "%vmovdqu")
+-		      : "%vmovdqa");
++	    opcode = TARGET_AVX512BW ? "vmovdqu16" : "%vmovdqu";
+ 	  break;
+ 	case E_SImode:
+ 	  if (evex_reg_p)
+-	    opcode = misaligned_p ? "vmovdqu32" : "vmovdqa32";
++	    opcode = "vmovdqu32";
+ 	  else
+-	    opcode = misaligned_p ? "%vmovdqu" : "%vmovdqa";
++	    opcode = "%vmovdqu";
+ 	  break;
+ 	case E_DImode:
+ 	case E_TImode:
+ 	case E_OImode:
+ 	  if (evex_reg_p)
+-	    opcode = misaligned_p ? "vmovdqu64" : "vmovdqa64";
++	    opcode = "vmovdqu64";
+ 	  else
+-	    opcode = misaligned_p ? "%vmovdqu" : "%vmovdqa";
++	    opcode = "%vmovdqu";
+ 	  break;
+ 	case E_XImode:
+-	  opcode = misaligned_p ? "vmovdqu64" : "vmovdqa64";
++	  opcode = "vmovdqu64";
+ 	  break;
+ 	default:
+ 	  gcc_unreachable ();