dlopen failed: empty/missing DT_HASH in "libx.so" (built with --hash-style=gnu?)

崩溃日志内容：

java.lang.UnsatisfiedLinkError: dlopen failed: empty/missing DT_HASH in "libxxxx.so" (built with --hash-style=gnu?)

 at java.lang.Runtime.loadLibrary(Runtime.java:371)

 at java.lang.System.loadLibrary(System.java:989)

崩溃设备信息：

{

    "STARTTIME": "1970-01-01 08:00:00",

    "CRASHTIME": "2015-08-14 01:47:28",

    "DEVICEID": "6aa3a6d0cbcb3251",

    "DEVICE": "hlte",

    "FINGERPRINT": "samsung/h3gduosctc/hlte:5.0/LRX21V/N9009KEU2GOF1:user/release-keys",

    "MODEL": "SM-N9009",

    "OSVERSION": "5.0",

    "CPU_ABI": "armeabi-v7a",

    "IMEI": "A00000443A46BD",

    "CPU_ABI2": "armeabi",

……

}

解决方案：
http://stackoverflow.com/questions/28638809/android-ndk-unsatisfiedlinkerror-dlopen-failed-empty-missing-dt-hash

The library you are trying to load was most likely built with Wl,hash-style=gnu. This was not supported on Android until recently (afaik this isn't even in L). You need to build your libraries with  -Wl,-hash-style=sysv.

How did you build cpplibrary.so? If you didn't do anything to manually switch to the gnu hash style, it could be a bug in the NDK.

One option is to add "LOCAL_LDFLAGS := -Wl,--hash-style=sysv" at screenrecord Android.mk though I am sure there is a less hacky method of doing so..

总结了一下是需要在Android.mk中添加链接选项：

LOCAL_LDFLAGS := Wl,-hash-style=sysv

libsysv-hash-table-library_ldflags := Wl,-hash-style=sysv

于是在修改前后查看了一下so节的变化：

readelf.exe -d libxxxx.so

Dynamic section at offset 0xed14 contains 27 entries:
Tag Type Name/Value
0x00000003 (PLTGOT) 0xfee0
0x00000002 (PLTRELSZ) 552 (bytes)
0x00000017 (JMPREL) 0x46fc
0x00000014 (PLTREL) REL
0x00000011 (REL) 0x39c4
0x00000012 (RELSZ) 3384 (bytes)
0x00000013 (RELENT) 8 (bytes)
0x6ffffffa (RELCOUNT) 420
0x00000006 (SYMTAB) 0x148
0x0000000b (SYMENT) 16 (bytes)
0x00000005 (STRTAB) 0x1918
0x0000000a (STRSZ) 5780 (bytes)
0x00000004 (HASH) 0x2fac
0x00000001 (NEEDED) Shared library: [liblog.so]
0x00000001 (NEEDED) Shared library: [libdl.so]
0x00000001 (NEEDED) Shared library: [libstdc++.so]
0x00000001 (NEEDED) Shared library: [libm.so]
0x00000001 (NEEDED) Shared library: [libc.so]
0x0000000e (SONAME) Library soname: [libbugrpt.so]
0x0000001a (FINI_ARRAY) 0xf590
0x0000001c (FINI_ARRAYSZ) 8 (bytes)
0x00000019 (INIT_ARRAY) 0xf598
0x0000001b (INIT_ARRAYSZ) 16 (bytes)
0x00000010 (SYMBOLIC) 0x0
0x0000001e (FLAGS) SYMBOLIC BIND_NOW
0x6ffffffb (FLAGS_1) Flags: NOW
0x00000000 (NULL) 0x0

readelf.exe -d libxxxx.so

Dynamic section at offset 0xed14 contains 27 entries:
Tag Type Name/Value
0x00000003 (PLTGOT) 0xfee0
0x00000002 (PLTRELSZ) 552 (bytes)
0x00000017 (JMPREL) 0x46fc
0x00000014 (PLTREL) REL
0x00000011 (REL) 0x39c4
0x00000012 (RELSZ) 3384 (bytes)
0x00000013 (RELENT) 8 (bytes)
0x6ffffffa (RELCOUNT) 420
0x00000006 (SYMTAB) 0x148
0x0000000b (SYMENT) 16 (bytes)
0x00000005 (STRTAB) 0x1918
0x0000000a (STRSZ) 5780 (bytes)
0x00000004 (HASH) 0x2fac
0x00000001 (NEEDED) Shared library: [liblog.so]
0x00000001 (NEEDED) Shared library: [libdl.so]
0x00000001 (NEEDED) Shared library: [libstdc++.so]
0x00000001 (NEEDED) Shared library: [libm.so]
0x00000001 (NEEDED) Shared library: [libc.so]
0x0000000e (SONAME) Library soname: [libbugrpt.so]
0x0000001a (FINI_ARRAY) 0xf590
0x0000001c (FINI_ARRAYSZ) 8 (bytes)
0x00000019 (INIT_ARRAY) 0xf598
0x0000001b (INIT_ARRAYSZ) 16 (bytes)
0x00000010 (SYMBOLIC) 0x0
0x0000001e (FLAGS) SYMBOLIC BIND_NOW
0x6ffffffb (FLAGS_1) Flags: NOW
0x00000000 (NULL) 0x0

修改前后的节并没有什么变化，然并卵啊！