Sylvain
After a long time, I found out more clearly what was going wrong.
The native libraries should be built with a "APP_PLATFORM" as low as possible.
Ideally, APP_PLATFORM should be equals to the minSdkVersion of the AndroidManifest.xml
So that the application never runs on a lower APP_PLATFORM than it has been built for.
An additional good patch would be to write explicitly in "jni/Application.mk": APP_PLATFORM=android-10
(If no APP_PLATFORM is set, the "targetSdkVersion" of the AndroidManifest.xml is applied as an APP_PLATFORM to the native libraries. And currently, this is bad, because targetSdkVersion is 12, whereas minSdkLevel is 10.
And in fact, there is a warning from ndk: "Android NDK: WARNING: APP_PLATFORM android-12 is larger than android:minSdkVersion 10 in ./AndroidManifest.xml".)
to precise what happened in the initial reported test-case:
Let say the "c" code contains a call to "srand()".
with APP_PLATFORM=android-21, libSDL2.so contains a undef reference to "srand()".
with APP_PLATFORM=android-10, libSDL2.so contains a undef reference to "srand48()".
but srand() is missing on devices with APP_PLATFORM=android-10 (it was in fact replaced by srand48()).
So, if you build for android-21 (where srand() is available), you will really have a call to "srand()" and it will fail on android-10.
That was the issue. The path tried to fix this by in fact always calling srand48().
SDL patches that were applied are beneficial anyway, there are implicitly allowing they backward compatibility of using android-21 on a android-10 platform.
It can be helpful in case you want to target a higher APP_PLATFORM than minSdkVersion to have potentially access to more functions.
Eg you want to have access to GLES3 functions (or other) of "android-21". But, if dlopen() fails (on android-10), you do a fall-back to GLES2.
Vitaly Novichkov
Line 124
====================================================================
const DWORD flags = thread->stacksize ? STACK_SIZE_PARAM_IS_A_RESERVATION : 0;
====================================================================
Error of compiler:
====================================================================
CC build/SDL_systhread.lo
src/thread/windows/SDL_systhread.c: In function 'SDL_SYS_CreateThread':
src/thread/windows/SDL_systhread.c:124:45: error: 'STACK_SIZE_PARAM_IS_A_RESERVA
TION' undeclared (first use in this function)
const DWORD flags = thread->stacksize ? STACK_SIZE_PARAM_IS_A_RESERVATION :
0;
^
src/thread/windows/SDL_systhread.c:124:45: note: each undeclared identifier is r
eported only once for each function it appears in
make: *** [build/SDL_systhread.lo] Error 1
====================================================================
Fixing when I adding into begin of the file:
====================================================================
#ifndef STACK_SIZE_PARAM_IS_A_RESERVATION
#define STACK_SIZE_PARAM_IS_A_RESERVATION 0x00010000
#endif
====================================================================
This allows us to set an explicit stack size (overriding the system default
and the global hint an app might have set), and remove all the macro salsa
for dealing with _beginthreadex and such, as internal threads always set those
to NULL anyhow.
I've taken some guesses on reasonable (and tiny!) stack sizes for our
internal threads, but some of these might turn out to be too small in
practice and need an increase. Most of them are simple functions, though.
We now only raise the magic exception that names the thread when
IsDebuggerPresent() returns true. In such a case, Visual Studio will
catch the exception, set the thread name, and let the debugged process
continue normally. If the debugger isn't running, we don't raise an exception
at all.
Setting the name is a debugger trick; if the debugger isn't running, the name
won't be set if attached later in any case, so this doesn't lose functionality.
This lets this code work without assembly code, on win32 and win64, and
across various compilers.
The only "gotcha" is that if you have something attached that looks like a
debugger but doesn't respect this magic exception trick, the process will
likely crash, but that's probably a deficiency of the attached program.
Fixes Bugzilla #2089.
WinRT 8.0 (Phone and non-Phone) didn't offer an API to set an already-created
thread's priority. WinRT 8.1 offered this API, along with several other
Win32 thread functions that were previously unavailable (in WinRT).
This change makes WinRT 8.1+ platforms use SDL's Win32 backend.
Sylvain
When using API 21 and running on an old device (android < 5.0 ?) some function are missing.
functions are (at least) : signal, sigemptyset, atof, stpcpy (strcat and strcpy), srand, rand.
Very few modifications on SDL to get this working :
on SDL
======
Undefine android configuration :
HAVE_SIGNAL
HAVE_SIGACTION
HAVE_ATOF
In "SDL_systrhead.c", comment out the few block of lines with "sigemptyset".
Android.mk:
remove the compilation of "test" directory because it contains a few rand/srand calls
Also, there are more discussions about this in internet :
https://groups.google.com/forum/#!topic/android-ndk/RjO9WmG9pfEhttp://stackoverflow.com/questions/25475055/android-ndk-load-library-cannot-locate-srand
Ozkan Sezer
pthread/SDL_syssem.c requires _GNU_SOURCE predefined (like SDL_sysmutex.c),
otherwise sem_timedwait() prototype might not be available to it. Problem
seen with glibc-2.3.4.
SDL 2.x recently accepted patches to enable OpenGL ES 2 support via Google's ANGLE library. The thought is to try to eventually merge SDL/WinRT's OpenGL code with SDL-official's.
Haiku uses most of the standard pthread API, with a few #ifdefs where we
still need to fallback onto the old BeOS APIs.
BeOS, however, does not support pthreads (or maybe doesn't support it well),
so I'm unplugging support for the platform with this changeset. Be Inc went
out of business in 2001.
