Fix compiler warnings in Native Client and Linux builds.

include/begin_code.h

@@ -41,6 +41,14 @@
 #  endif
 #endif
 
+#ifndef SDL_UNUSED
+#  ifdef __GNUC__
+#    define SDL_UNUSED __attribute__((unused))
+#  else
+#    define SDL_UNUSED
+#  endif
+#endif
+
 /* Some compilers use a special export keyword */
 #ifndef DECLSPEC
 # if defined(__WIN32__) || defined(__WINRT__)

src/audio/SDL_wave.c

@@ -121,7 +121,8 @@ MS_ADPCM_decode(Uint8 ** audio_buf, Uint32 * audio_len)
     struct MS_ADPCM_decodestate *state[2];
     Uint8 *freeable, *encoded, *decoded;
     Sint32 encoded_len, samplesleft;
-    Sint8 nybble, stereo;
+    Sint8 nybble;
+    Uint8 stereo;
     Sint16 *coeff[2];
     Sint32 new_sample;
 
@@ -278,7 +279,8 @@ IMA_ADPCM_nibble(struct IMA_ADPCM_decodestate *state, Uint8 nybble)
     } else if (state->index < 0) {
         state->index = 0;
     }
-    step = step_table[state->index];
+    /* explicit cast to avoid gcc warning about using 'char' as array index */
+    step = step_table[(int)state->index];
     delta = step >> 3;
     if (nybble & 0x04)
         delta += step;

src/stdlib/SDL_iconv.c

@@ -32,7 +32,8 @@
    If we get this wrong, it's just a warning, so no big deal.
 */
 #if defined(_XGP6) || defined(__APPLE__) || \
-    (defined(__GLIBC__) && ((__GLIBC__ > 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 2)))
+    (defined(__GLIBC__) && ((__GLIBC__ > 2) || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 2)) || \
+    (defined(_NEWLIB_VERSION)))
 #define ICONV_INBUF_NONCONST
 #endif
 

src/test/SDL_test_harness.c

@@ -564,7 +564,7 @@ int SDLTest_RunSuites(SDLTest_TestSuiteReference *testSuites[], const char *user
                             execKey = SDLTest_GenerateExecKey((char *)runSeed, testSuite->name, testCase->name, iterationCounter);
                         }
 
-                        SDLTest_Log("Test Iteration %i: execKey %llu", iterationCounter, (long long unsigned)execKey);
+                        SDLTest_Log("Test Iteration %i: execKey %" PRIu64, iterationCounter, execKey);
                         testResult = SDLTest_RunTest(testSuite, testCase, execKey);
 
                         if (testResult == TEST_RESULT_PASSED) {

src/thread/pthread/SDL_sysmutex.c

@@ -20,7 +20,9 @@
 */
 #include "../../SDL_internal.h"
 
+#ifndef _GNU_SOURCE
 #define _GNU_SOURCE
+#endif
 #include <pthread.h>
 #include <errno.h>
 

src/thread/pthread/SDL_systhread.c

@@ -57,11 +57,13 @@
 
 #include "SDL_assert.h"
 
+#ifndef __NACL__
 /* List of signals to mask in the subthreads */
 static const int sig_list[] = {
     SIGHUP, SIGINT, SIGQUIT, SIGPIPE, SIGALRM, SIGTERM, SIGCHLD, SIGWINCH,
     SIGVTALRM, SIGPROF, 0
 };
+#endif
 
 static void *
 RunThread(void *data)
@@ -115,8 +117,10 @@ SDL_SYS_CreateThread(SDL_Thread * thread, void *args)
 void
 SDL_SYS_SetupThread(const char *name)
 {
+#ifndef __NACL__
     int i;
     sigset_t mask;
+#endif
 
     if (name != NULL) {
         #if defined(__MACOSX__) || defined(__IPHONEOS__) || defined(__LINUX__)

src/timer/unix/SDL_systimer.c

@@ -28,6 +28,7 @@
 #include <errno.h>
 
 #include "SDL_timer.h"
+#include "SDL_assert.h"
 
 /* The clock_gettime provides monotonous time, so we should use it if
    it's available. The clock_gettime function is behind ifdef
@@ -106,6 +107,9 @@ SDL_GetTicks(void)
 #elif defined(__APPLE__)
         uint64_t now = mach_absolute_time();
         ticks = (((now - start_mach) * mach_base_info.numer) / mach_base_info.denom) / 1000000;
+#else
+        SDL_assert(SDL_FALSE);
+        ticks = 0;
 #endif
     } else {
         struct timeval now;
@@ -136,6 +140,9 @@ SDL_GetPerformanceCounter(void)
         ticks += now.tv_nsec;
 #elif defined(__APPLE__)
         ticks = mach_absolute_time();
+#else
+        SDL_assert(SDL_FALSE);
+        ticks = 0;
 #endif
     } else {
         struct timeval now;

src/video/SDL_blit_A.c

@@ -343,7 +343,7 @@ BlitRGBtoRGBPixelAlphaMMX(SDL_BlitInfo * info)
     mm_zero = _mm_setzero_si64();       /* 0 -> mm_zero */
     multmask = 0x00FF;
 	multmask <<= (ashift * 2);
-	multmask2 = 0x00FF00FF00FF00FF;
+	multmask2 = 0x00FF00FF00FF00FFULL;
 
     while (height--) {
 		/* *INDENT-OFF* */
@@ -530,7 +530,7 @@ BlitRGBtoRGBPixelAlphaMMX3DNOW(SDL_BlitInfo * info)
     mm_zero = _mm_setzero_si64();       /* 0 -> mm_zero */
     multmask = 0x00FF;
     multmask <<= (ashift * 2);
-    multmask2 = 0x00FF00FF00FF00FF;
+    multmask2 = 0x00FF00FF00FF00FFULL;
 
     while (height--) {
 	    /* *INDENT-OFF* */

src/video/SDL_video.c

@@ -3259,7 +3259,8 @@ SDL_IsScreenKeyboardShown(SDL_Window *window)
 #include "x11/SDL_x11messagebox.h"
 #endif
 
-static SDL_bool SDL_MessageboxValidForDriver(const SDL_MessageBoxData *messageboxdata, SDL_SYSWM_TYPE drivertype)
+// This function will be unused if none of the above video drivers are present.
+SDL_UNUSED static SDL_bool SDL_MessageboxValidForDriver(const SDL_MessageBoxData *messageboxdata, SDL_SYSWM_TYPE drivertype)
 {
     SDL_SysWMinfo info;
     SDL_Window *window = messageboxdata->window;

src/video/nacl/SDL_naclwindow.c

@@ -24,6 +24,8 @@
 
 #include "../SDL_sysvideo.h"
 
+#include "../../events/SDL_mouse_c.h"
+#include "../../events/SDL_keyboard_c.h"
 #include "SDL_naclvideo.h"
 #include "SDL_naclwindow.h"