recipes: scipy - fix build for armeabi-v7a (kivy#2402)

* fix for armeabi-v7a
* move comment to docstring

Author: mzakharo

pythonforandroid/recipes/lapack/__init__.py

@@ -1,3 +1,8 @@
+'''
+known to build with cmake version 3.19.2 and NDK r19c.
+See https://gitlab.kitware.com/cmake/cmake/-/issues/18739
+'''
+
 from pythonforandroid.recipe import Recipe
 from pythonforandroid.logger import shprint
 from pythonforandroid.util import current_directory, ensure_dir, BuildInterruptingException

pythonforandroid/recipes/scipy/__init__.py

@@ -26,7 +26,7 @@ def get_recipe_env(self, arch):
 
         GCC_VER = '4.9'
         HOST = 'linux-x86_64'
-        LIB = 'lib64'
+        LIB = 'lib64' if '64' in arch.arch else 'lib'
 
         prefix = env['TOOLCHAIN_PREFIX']
         lapack_dir = join(Recipe.get_recipe('lapack', self.ctx).get_build_dir(arch.arch), 'build', 'install')
@@ -43,6 +43,8 @@ def get_recipe_env(self, arch):
         env['CPPFLAGS'] += f' --sysroot={sysroot} -I{sysroot_include}/c++/v1 -I{sysroot_include}'
         env['LDSHARED'] = 'clang'
         env['LDFLAGS'] += f' {LDSHARED_opts} --sysroot={sysroot} -L{libgfortran} -L{numpylib}'
+        env['LDFLAGS'] += f' -L{self.ctx.ndk_dir}/sources/cxx-stl/llvm-libc++/libs/{arch.arch}/'
+
         return env