diff -Nru libcrypto++-8.6.0/debian/changelog libcrypto++-8.6.0/debian/changelog
--- libcrypto++-8.6.0/debian/changelog	2022-02-12 09:39:14.000000000 +0000
+++ libcrypto++-8.6.0/debian/changelog	2022-03-19 22:09:41.000000000 +0000
@@ -1,3 +1,14 @@
+libcrypto++ (8.6.0-3+rpi1) bookworm-staging; urgency=medium
+
+  * Upload to raspbian despite detection of armv7 contaimination,
+    investigation of the code shows that the armv7/neon code seems
+    to be safely behind runtime CPU testection.
+  * Pass -march=armv7+fp instead of -march=armv7 when building "armv4"
+    assembler files. Despite the names these files only seem to be used
+    on armv7.
+
+ -- Peter Michael Green <plugwash@raspbian.org>  Sat, 19 Mar 2022 22:09:41 +0000
+
 libcrypto++ (8.6.0-3) unstable; urgency=medium
 
   * Fix armhf FTBFS (closes: #1001995). 
diff -Nru libcrypto++-8.6.0/debian/patches/series libcrypto++-8.6.0/debian/patches/series
--- libcrypto++-8.6.0/debian/patches/series	2022-02-12 09:39:14.000000000 +0000
+++ libcrypto++-8.6.0/debian/patches/series	2022-03-19 22:09:41.000000000 +0000
@@ -1,3 +1,4 @@
 GNUmakefile_update.patch
 armhf_FTBFS_fix.patch
 fix_library_name.patch
+use-fp-with-march.patch
diff -Nru libcrypto++-8.6.0/debian/patches/use-fp-with-march.patch libcrypto++-8.6.0/debian/patches/use-fp-with-march.patch
--- libcrypto++-8.6.0/debian/patches/use-fp-with-march.patch	1970-01-01 00:00:00.000000000 +0000
+++ libcrypto++-8.6.0/debian/patches/use-fp-with-march.patch	2022-03-19 22:09:41.000000000 +0000
@@ -0,0 +1,22 @@
+Description:  pass -march=armv7+fp when building "armv4" assembler files.
+ despite the names these only seem to be used for armv7, and contain
+ neon implementations which won't be built if no -march is specified
+Author: Peter Michael Green <plugwash@raspbian.org>
+
+Index: libcrypto++-8.6.0/GNUmakefile
+===================================================================
+--- libcrypto++-8.6.0.orig/GNUmakefile
++++ libcrypto++-8.6.0/GNUmakefile
+@@ -1181,11 +1181,7 @@ endif
+ # Also see https://www.cryptopp.com/wiki/Cryptogams.
+ ifeq ($(IS_ARM32)$(IS_LINUX),11)
+   ifeq ($(filter -DCRYPTOPP_DISABLE_ASM -DCRYPTOPP_DISABLE_ARM_NEON,$(CPPFLAGS)$(CXXFLAGS)),)
+-    # Do not use -march=armv7 if the compiler is already targeting the ISA.
+-    # Also see https://github.com/weidai11/cryptopp/issues/1094
+-    ifneq ($($(CXX) ++ -dM -E - </dev/null 2>/dev/null| grep 'ARM_ARCH 7|_ARM_ARCH_7A__'),)
+-      CRYPTOGAMS_ARMV7_FLAG = -march=armv7-a
+-    endif
++    CRYPTOGAMS_ARMV7_FLAG = -march=armv7-a+fp
+     ifeq ($(CLANG_COMPILER),1)
+       CRYPTOGAMS_ARM_FLAG = $(CRYPTOGAMS_ARMV7_FLAG)
+       CRYPTOGAMS_ARM_THUMB_FLAG = $(CRYPTOGAMS_ARMV7_FLAG) -mthumb