When compiled for arm with -mfpu=neon, the .init_array section declared

here becomes 64-bit aligned. Since the dynamic linker expects an array of

32-bit function pointers with no gaps, this causes an immediate SIGSEGV

for any application linked with libdl.

I suspect the default array alignment becomes 64 bits because the neon

has 64-bit registers, but I'm not sure. The explicit aligned attribute

does not help because it can only increase the alignment.

Fortunately, the whole declaration can be replaced with a constructor

attribute on the init function, which also adds it to the init_array

table and does the right thing with alignment.

(Why wasn't it this way already? I don't know, but maybe the constructor

attribute wasn't available yet when this code was written.)

Richard Braakman

richard.braakman@jollamobile.com

--- eglibc-2.15/dlfcn/dlfcn.c 2006-08-17 04:18:26.000000000 +0300

+++ glibc-fixed/dlfcn/dlfcn.c 2013-06-10 13:20:34.846885906 +0300

@@ -24,16 +24,9 @@

char **__dlfcn_argv attribute_hidden;

-static void

+static void __attribute ((constructor))

init (int argc, char *argv[])

{

__dlfcn_argc = argc;

__dlfcn_argv = argv;

}

-

-static void (*const init_array []) (int argc, char *argv[])

- __attribute__ ((section (".init_array"), aligned (sizeof (void *))))

- __attribute_used__ =

-{

- init

-};