armv7l build support (#2601)

* Fixes from Bitcoin #12474

This commit fixes building of boost and openssl on armv7l as described in Bitcoin issue #12474

* Prevent compiler from emitting illegal instructions to armv7l CPUs

* Limit dwsize for armv7l

* Remove superfluous cppflags argument

depends/Makefile

@@ -21,7 +21,6 @@ BUILD_ID_SALT ?= salt
 host:=$(BUILD)
 ifneq ($(HOST),)
 host:=$(HOST)
-host_toolchain:=$(HOST)-
 endif
 
 ifneq ($(DEBUG),)

depends/hosts/default.mk

@@ -1,3 +1,7 @@
+ifneq ($(host),$(build))
+host_toolchain:=$(host)-
+endif
+
 default_host_CC = $(host_toolchain)gcc
 default_host_CXX = $(host_toolchain)g++
 default_host_AR = $(host_toolchain)ar

depends/packages/chia_bls.mk

@@ -21,6 +21,7 @@ define $(package)_set_vars
   $(package)_config_opts_i686+= -DWSIZE=32
   $(package)_config_opts_x86_64+= -DWSIZE=64
   $(package)_config_opts_arm+= -DWSIZE=32
+  $(package)_config_opts_armv7l+= -DWSIZE=32
   $(package)_config_opts_debug=-DDEBUG=ON -DCMAKE_BUILD_TYPE=Debug
 
   ifneq ($(darwin_native_toolchain),)

depends/packages/gmp.mk

@@ -6,6 +6,7 @@ $(package)_sha256_hash=5275bb04f4863a13516b2f39392ac5e272f5e1bb8057b18aec1c9b79d
 
 define $(package)_set_vars
 $(package)_config_opts+=--enable-cxx --enable-fat --with-pic --disable-shared
+$(package)_cflags_armv7l_linux+=-march=armv7-a
 endef
 
 define $(package)_config_cmds

depends/packages/openssl.mk

@@ -47,6 +47,7 @@ $(package)_config_opts_linux=-fPIC -Wa,--noexecstack
 $(package)_config_opts_x86_64_linux=linux-x86_64
 $(package)_config_opts_i686_linux=linux-generic32
 $(package)_config_opts_arm_linux=linux-generic32
+$(package)_config_opts_armv7l_linux=linux-generic32
 $(package)_config_opts_aarch64_linux=linux-generic64
 $(package)_config_opts_mipsel_linux=linux-generic32
 $(package)_config_opts_mips_linux=linux-generic32