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Linker errors with external NDK library that needs 'cpufeatures'

I'm trying to build and link freeimage to an android project. I'm close but I'm tripping up on some linker errors from that library.
I'm using this repo: https://github.com/jamcar23/FreeImage-Android/blob/master/jni/freeimage/Android.mk
Freeimage uses the internal NDK library 'cpufeatures' to use xeon chipset features. In the project's 'android.mk', there's a reference to the cpufeatures library:
LOCAL_STATIC_LIBRARIES := cpufeatures
and my library, which statically links to this one, also includes cpufeatures in its LOCAL_STATIC_LIBRARIES statement in that project's android.mk:
LOCAL_STATIC_LIBRARIES := tinyxml freetype2 bullet freeimage cpufeatures
also in my android.mk, I link freeimage like this:
#####FREEIMAGE_LIBRARY_DECLARATION##########
include $(CLEAR_VARS)
LOCAL_PATH = $(TPLIBROOT)/FreeImage-Android
LOCAL_MODULE := freeimage
LOCAL_EXPORT_C_INCLUDES := include
LOCAL_SRC_FILES := obj/local/$(TARGET_ARCH_ABI)/libFreeImage.a
include $(PREBUILT_STATIC_LIBRARY)
###############################################
which, taking note of a previous question I had about the NDK, should take care of specific architectures (I've build freeimage using all available architectures)
freeimage .a and .so libraries appear to build fine but on linking to my library when building the .so, I get this error:
[armeabi-v7a] SharedLibrary : libAnthracite.so
jni/freeimage/Source/LibWebP/./src/dsp/dsp.cpu.c:108: error: undefined reference to 'android_getCpuFamily'
jni/freeimage/Source/LibWebP/./src/dsp/dsp.cpu.c:109: error: undefined reference to 'android_getCpuFeatures'
jni/freeimage/Source/LibWebP/./src/dsp/dsp.dec.c:745: error: undefined reference to 'VP8DspInitNEON'
which is odd as both libraries do link cpufeatures, so it really ought to be there.
I'm declaring
APP_PLATFORM := android-14
APP_STL := gnustl_static
in the application.mk files for both projects.
Also, I've tried placing 'LOCAL_STATIC_LIBRARIES' in different positions in the files and linking libraries in different orders, although that's just guesswork.
Does anybody know what might be causing these linker errors?

Please follow the official guide to add cpu-features. TL;NR: add $(call import-module,android/cpufeatures) to your Android.mk.

I finally got it to work by ensuring that all of my 'application.mk' files for all four of the third party libraries I was using shared a common base file that looks like this:
APP_PLATFORM := android-15
APP_STL := c++_static
APP_ABI := all
APP_OPTIM := release
APP_SHORT_COMMANDS := true
Which makes keeping them in line easier, ensuring they're all built against the same libraries.
Also, I changed the STL implementation from 'gnustl_static' to 'c++_static'

Android can't include linux in C program with Android.mk

I'm trying to compile a C program for Android 6. This is my Android.mk:
APP_PLATFORM := android-23
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
# Enable PIE manually. Will get reset on $(CLEAR_VARS). This
# is what enabling PIE translates to behind the scenes.
LOCAL_CFLAGS += -fPIE -DHAVE_FANOTIFY=1 -DHAVE_SYS_FANOTIFY=0
LOCAL_LDFLAGS += -fPIE -pie
# give module name
LOCAL_MODULE := fsmon
# list your C files to compile
LOCAL_SRC_FILES := inotify.c fanotify.c util.c main.c
# this option will build executables instead of building library for android application.
include $(BUILD_EXECUTABLE)
In the fanotify.c following include is written:
#include <linux/fanotify.h>
When I try to use ndk-build, following error appears:
fsmon/jni/fanotify.c:51:10: fatal error: 'linux/fanotify.h' file not found
#include <linux/fanotify.h>
^
The header fanotify.h is present in the ndk path /Android/Sdk/ndk-bundle/sysroot/usr/include/linux
Any suggestions?
EDIT: Same error if I try to include sys/fanotify.h

You can specify additional include paths for your module using LOCAL_C_INCLUDES.
LOCAL_C_INCLUDES := /Android/Sdk/ndk-bundle/sysroot/usr/include/
https://developer.android.com/ndk/guides/android_mk.html#mdv

The NDK historically didn't backport headers to old releases, but we've reworked things in r14 so this is possible: https://android.googlesource.com/platform/ndk/+/ndk-r14-release/docs/UnifiedHeaders.md
By default in r14 you still get the old form of the headers. The new "unified headers" have the headers you're looking for. If you want to try unified headers, set APP_UNIFIED_HEADERS := true in your Application.mk (settings for other build systems can be found in the link above).
In r15 (first beta due out soon), the default has changed to the new headers, and the option for disabling them has changed (see the same doc in r15 for changes in options: https://android.googlesource.com/platform/ndk/+/ndk-r15-release/docs/UnifiedHeaders.md).

How to resolve "Relocations in Generic ELF" during ndk-build?

I'm trying to build a static library using a standalone toolchain for a project that has its own build process, which I then wrap with a C++ library and expose to Android (compiled with ndk-build). However, on the ndk-build step I receive the following error:
➜ jni /Users/chrisfosterelli/Library/Android/sdk/ndk-bundle/ndk-build
[arm64-v8a] Compile++ : wrapper <= wrapper.cpp
In file included from /Users/chrisfosterelli/workspace/android/jni/wrapper.cpp:9:
In file included from ../prebuild/include/valhalla/meili/universal_cost.h:7:
In file included from ../prebuild/include/valhalla/sif/dynamiccost.h:4:
In file included from ../prebuild/include/valhalla/baldr/directededge.h:5:
../prebuild/include/valhalla/baldr/graphconstants.h:432:11: warning: 21 enumeration values not handled in switch: 'kRoad', 'kRamp', 'kTurnChannel'... [-Wswitch]
switch (use) {
^
1 warning generated.
[arm64-v8a] SharedLibrary : libwrapper.so
/Users/chrisfosterelli/Library/Android/sdk/ndk-bundle/toolchains/aarch64-linux-android-4.9/prebuilt/darwin-x86_64/lib/gcc/aarch64-linux-android/4.9.x/../../../../aarch64-linux-android/bin/ld: /Users/chrisfosterelli/workspace/android/jni/../prebuild/libvalhalla_meili.a(libvalhalla_meili_la-map_matcher_factory.o): Relocations in generic ELF (EM: 62)
[...above message repeated many times...]
/Users/chrisfosterelli/workspace/android/jni/../prebuild/libvalhalla_meili.a: error adding symbols: File in wrong format
clang++: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [/Users/chrisfosterelli/workspace/android/obj/local/arm64-v8a/libwrapper.so] Error 1
➜ jni ls /Users/chrisfosterelli/Library/Android/sdk/ndk-bundle/
This error indicates, as far as I can tell, that I'm trying to mix and match binaries compiled for different architectures. However, from what I can tell the library is the correct architecture:
root#eacbdb1c0e46:/meili/meili2/newtest# ar x libvalhalla_meili.a
root#eacbdb1c0e46:/meili/meili2/newtest# file libvalhalla_meili_la-map_matcher_factory.o
libvalhalla_meili_la-map_matcher_factory.o: ELF 64-bit LSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
root#eacbdb1c0e46:/meili/meili2/newtest#
FWIW, these are my current Application.mk,
APP_STL := c++_static
APP_CPPFLAGS := -frtti -std=gnu++11 -D_GLIBCXX_USE_C99
APP_CPPFLAGS += -fexceptions
NDK_TOOLCHAIN_VERSION := clang
APP_LDFLAGS := -latomic
APP_PLATFORM := android-21
APP_ABI := arm64-v8a
and Android.mk,
LOCAL_PATH := $(call my-dir)
# static library info
include $(CLEAR_VARS)
LOCAL_MODULE := libvalhalla_meili
LOCAL_SRC_FILES := ../prebuild/libvalhalla_meili.a
LOCAL_EXPORT_C_INCLUDES := ../prebuild/include
include $(PREBUILT_STATIC_LIBRARY)
# wrapper info
include $(CLEAR_VARS)
LOCAL_C_INCLUDES += ../prebuild/include
LOCAL_MODULE := wrapper
LOCAL_SRC_FILES := wrapper.cpp
LOCAL_STATIC_LIBRARIES := libvalhalla_meili
include $(BUILD_SHARED_LIBRARY)
Any ideas how to resolve this? I've tried a number of things but all of them lead to more (more obscure) errors, so I'm hoping someone here can point me in the correct direction!

I discovered the problem, but I wish I had a more insightful answer. Apparently the build process had created two library files. The one that I inspected was, of course, ARM64. However the one that I actually copied to the Android device was x86.
So, the error message was correct and so was the library file, but there was more than one file involved. If you're running into the same problem and pretty sure your library is ARM64, double check that's actually the same file that is being compiled into the ndk build!

use libcryto.so and libssl.so in an android project?

I'm beginer to Android NDK. I want to build a RSA example base on openssl libary.
First, I built libssl.so and libcrypto.so librairies with ndk-build in the guardianproject.
Next, I create a new sample project to integrate libary (libss.so & lybcryto.so). I follow the same in this post
My App directory
TrialApp
|
|-->Activity.java (includes System.LoadLibrary calls)
|
|-->jni
|-->TestJNI2.cpp
|
|-->Android.mk
|
|-->includes
| |
| |-->openssl (dir containing *.h files)
|
|-->precompiled
|-->libssl.so
|-->libcrypto.so
My android.mk:
LOCAL_PATH := $(call my-dir)
# Prebuilt libssl
include $(CLEAR_VARS)
LOCAL_MODULE := ssl
LOCAL_SRC_FILES := precompiled/libssl.so
include $(PREBUILT_SHARED_LIBRARY)
# Prebuilt libcrypto
include $(CLEAR_VARS)
LOCAL_MODULE := crypto
LOCAL_SRC_FILES := precompiled/libcrypto.so
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
c_includes := $(LOCAL_PATH)
cf_includes := includes/openssl
cf_includes := $(addprefix -Ijni/,$(cf_includes))
export_c_includes := $(c_includes)
LOCAL_MODULE := security
LOCAL_SRC_FILES := TestJNI2.cpp
LOCAL_CFLAGS += $(cf_includes)
LOCAL_EXPORT_C_INCLUDES := $(export_c_includes)
LOCAL_LDLIBS := -llog
LOCAL_LDLIBS += $(LOCAL_PATH)/precompiled/libssl.so
LOCAL_LDLIBS += $(LOCAL_PATH)/precompiled/libcrypto.so
include $(BUILD_SHARED_LIBRARY)
TestJNI2.cpp
/* OpenSSL headers */
#include "openssl/bio.h"
#include "openssl/ssl.h"
#include "openssl/err.h"
/* Initializing OpenSSL */
void init_openssl(void){
SSL_load_error_strings();
ERR_load_BIO_strings();
OpenSSL_add_all_algorithms();
}
Then when i build with ndk-build always have problems like this
/data/workspace/TestJNI2/jni/TestJNI2.cpp:3:25: error: openssl/bio.h: No such file or directory
/data/workspace/TestJNI2/jni/TestJNI2.cpp:4:25: error: openssl/ssl.h: No such file or directory
/data/workspace/TestJNI2/jni/TestJNI2.cpp:5:25: error: openssl/err.h: No such file or directory
/data/workspace/TestJNI2/jni/TestJNI2.cpp: In function 'void init_openssl()':
/data/workspace/TestJNI2/jni/TestJNI2.cpp:10: error: 'SSL_load_error_strings' was not declared in this scope
/data/workspace/TestJNI2/jni/TestJNI2.cpp:11: error: 'ERR_load_BIO_strings' was not declared in this scope
/data/workspace/TestJNI2/jni/TestJNI2.cpp:12: error: 'OpenSSL_add_all_algorithms' was not declared in this scope
make: *** [/data/workspace/TestJNI2/obj/local/armeabi/objs/security/TestJNI2.o] Error 1
Can anyone help me? Or how to build an example RSA algorthim base on openssl lib?

You should build static libraries for libssl and libcrypto in your script. If you can't, rename these libraries (you can do this after build, while copying to your precompiled directory). The reason is that the system comes with its own (probably different) version of these shared libraries, and the loader will use /system/lib/libssl.so and /system/lib/libcrypto.so instead of your private copies.
Regarding the Android.mk file, I slightly cleaned it up for you (note that I did not change the names of prebuilt LOCAL_MODULEs, but changed the name of LOCAL_MODULE you finally build, because security is, well, too generic and could also happen to match a system library on some device):
LOCAL_PATH := $(call my-dir)
# Prebuilt libssl
include $(CLEAR_VARS)
LOCAL_MODULE := ssl
LOCAL_SRC_FILES := precompiled/libPrivateSsl.so
include $(PREBUILT_SHARED_LIBRARY)
# Prebuilt libcrypto
include $(CLEAR_VARS)
LOCAL_MODULE := crypto
LOCAL_SRC_FILES := precompiled/libPrivateCrypto.so
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := PrivateSecurity
LOCAL_C_INCLUDES := includes
LOCAL_SRC_FILES := TestJNI2.cpp
LOCAL_LDLIBS := -llog
LOCAL_SHARED_LIBRARIES := ssl crypto
include $(BUILD_SHARED_LIBRARY)
Don't forget that your Java should load the dependencies first:
{
System.loadLibrary("PrivateSsl");
System.loadLibrary("PrivateCrypto");
System.loadLibrary("PrivateSecurity");
}

I'm beginer to Android NDK. I want to build a RSA example base on openssl libary.
You can, but you have to be careful. Here's the reason Alex told you to use static libraries for libssl and libcrypto in your script.
The master Android process is zygote. Its like init in Linux. Zygote loads OpenSSL when its start, and it loads version 0.9.8. If you link against OpenSSL 1.0.1, then you will get mysterious runtime crashes. The crashes are due to the Android loader using the 0.9.8 version of the library (already mapped from Zygote), and not your version of OpenSSL.
You can use a shared object, but your shared object must be a wrapper around the static version of libssl and libcrypto.
If you are not using Android's build system, then you can find additional instructions for building purely from the command line at OpenSSL's wiki. The wiki page includes setting the envrionment and cross compiling. See FIPS Library and Android.
Another thing to watch out for: be sure to build with -mfloat-abi=softfp. The stock OpenSSL misses that when cross compiling. You need it to ensure floats are passed on the stack, and not through floating point registers. Otherwise, all your floats will mysteriously have 0.0f value (like the floats used to estimate entropy in RAND_add).

Error: selected processor does not support ARM mode

I'm trying to build a jni project which generates a shared library using the Android-ndk.
I'm going to code a some part in assembly language as needed, so I configured the project as the following.
Android.mk:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := my_test
LOCAL_SRC_FILES := Test.cpp MyAsm.s
LOCAL_CFLAGS :=
include $(BUILD_SHARED_LIBRARY)
Application.mk:
APP_ABI := armeabi-v7a
APP_STL := stlport_static
Test.cpp:
...
MyAsmFunc();
...
MyAsm.s:
.text
.align 2
.global MyAsmFunc
MyAsmFunc:
...
tbb [PC,R1]
...
cbnz R1,loc_51ACE
...
When I was compiling the project, I've got the following error msg.
MyAsm.s:224: Error: selected processor does not support ARM mode `tbb [PC,R1]'
MyAsm.s:882: Error: selected processor does not support ARM mode `cbnz R1,loc_51ACE'
My question is how to build the project successful. Help me, please.
Thanks in advance.

According to this page,
These 16-bit Thumb instructions are available in ARMv6T2 and above.
There are no ARM or 32-bit Thumb versions of these instructions.
You're compiling for ARMv7-A, so the first part is fine. However, it's trying to interpret the instructions as ARM rather than THUMB/THUMB2. Add .thumb / .thumb_func directives to your assembly source file to set THUMB mode. See also the GNU as docs.