Compile libv8 on ARMv7 HF vfpv3 32bits

ext/libv8/builder.rb

@@ -25,7 +25,7 @@ module Libv8
       flags << "strictaliasing=off" if @compiler.is_a?(Compiler::GCC) and @compiler.version < '4.4'
 
       # Avoid compilation failures on the Raspberry Pi.
-      flags << "vfp2=off vfp3=off" if @compiler.target.include? "arm"
+      flags << "vfp2=off vfp3=on" if @compiler.target.include? "arm"
 
       # FIXME: Determine when to activate this instead of leaving it on by
       # default.

patches/arm/do-not-use-vfp2.patch

@@ -0,0 +1,13 @@
+diff --git a/build/common.gypi b/build/common.gypi
+index 3a59639..594abe4 100644
+--- a/build/common.gypi
++++ b/build/common.gypi
+@@ -173,7 +173,6 @@
+           [ 'v8_use_arm_eabi_hardfloat=="true"', {
+             'defines': [
+               'USE_EABI_HARDFLOAT=1',
+-              'CAN_USE_VFP2_INSTRUCTIONS',
+             ],
+             'target_conditions': [
+               ['_toolset=="target"', {
+

patches/fPIC-for-static.patch

@@ -7,7 +7,7 @@ index 125c5bf..71641a3 100644
              'cflags': [ '-fvisibility=hidden' ],
            }],
 -          [ 'component=="shared_library"', {
-+          [ 'component=="shared_library" or component=="static_library" and v8_target_arch=="x64"', {
++          [ 'component=="shared_library" or component=="static_library" and v8_target_arch=="x64" or v8_target_arch=="arm"', {
              'cflags': [ '-fPIC', ],
            }],
          ],