Use C11 alignas when available

Alc/align.h

@@ -0,0 +1,21 @@
+#ifndef AL_ALIGN_H
+#define AL_ALIGN_H
+
+#ifdef HAVE_STDALIGN_H
+#include <stdalign.h>
+#endif
+
+#ifndef alignas
+#ifdef HAVE_C11_ALIGNAS
+#define alignas _Alignas
+#elif defined(IN_IDE_PARSER)
+/* KDevelop has problems with our align macro, so just use nothing for parsing. */
+#define alignas(x)
+#else
+/* NOTE: Our custom ALIGN macro can't take a type name like alignas can. For
+ * maximum compatibility, only provide constant integer values to alignas. */
+#define alignas(_x) ALIGN(_x)
+#endif
+#endif
+
+#endif /* AL_ALIGN_H */

Alc/mixer_inc.c

@@ -2,8 +2,10 @@
 
 #include "alMain.h"
 #include "alSource.h"
+
 #include "hrtf.h"
 #include "mixer_defs.h"
+#include "align.h"
 
 
 #define REAL_MERGE2(a,b) a##b
@@ -36,7 +38,7 @@ void MixDirect_Hrtf(DirectParams *params, const ALfloat *restrict data, ALuint s
     ALfloat (*restrict Values)[2] = params->Mix.Hrtf.State.Values[srcchan];
     ALuint Counter = maxu(params->Counter, OutPos) - OutPos;
     ALuint Offset = params->Offset + OutPos;
-    ALIGN(16) ALfloat Coeffs[HRIR_LENGTH][2];
+    alignas(16) ALfloat Coeffs[HRIR_LENGTH][2];
     ALuint Delay[2];
     ALfloat left, right;
     ALuint pos;

CMakeLists.txt

@@ -176,6 +176,15 @@ CHECK_C_SOURCE_COMPILES(
  }"
 HAVE_C11_STATIC_ASSERT)
 
+# Check if we have C11 alignas
+CHECK_C_SOURCE_COMPILES(
+"_Alignas(4) int foo;
+ int main()
+ {
+     return 0;
+ }"
+HAVE_C11_ALIGNAS)
+
 # Add definitions, compiler switches, etc.
 INCLUDE_DIRECTORIES("${OpenAL_SOURCE_DIR}/include" "${OpenAL_BINARY_DIR}")
 IF(CMAKE_VERSION VERSION_LESS "2.8.8")
@@ -319,6 +328,7 @@ ENDIF()
 CHECK_C_SOURCE_COMPILES("int foo(const char *str, ...) __attribute__((format(printf, 1, 2)));
                          int main() {return 0;}" HAVE_GCC_FORMAT)
 
+CHECK_INCLUDE_FILE(stdalign.h HAVE_STDALIGN_H)
 IF(NOT HAVE_C99_VLA)
     CHECK_INCLUDE_FILE(alloca.h HAVE_ALLOCA_H)
 ENDIF()

OpenAL32/Include/alAuxEffectSlot.h

@@ -4,6 +4,8 @@
 #include "alMain.h"
 #include "alEffect.h"
 
+#include "align.h"
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -72,7 +74,7 @@ typedef struct ALeffectslot {
     volatile ALenum NeedsUpdate;
     ALeffectState *EffectState;
 
-    ALIGN(16) ALfloat WetBuffer[1][BUFFERSIZE];
+    alignas(16) ALfloat WetBuffer[1][BUFFERSIZE];
 
     RefCount ref;
 

OpenAL32/Include/alMain.h

@@ -31,7 +31,7 @@
 #endif
 #endif
 
-
+#include "align.h"
 #include "atomic.h"
 #include "uintmap.h"
 #include "vector.h"
@@ -271,11 +271,6 @@ ALC_API void ALC_APIENTRY alcGetInteger64vSOFT(ALCdevice *device, ALCenum pname,
 /* KDevelop's parser doesn't recognize the C99-standard restrict keyword, but
  * recent versions (at least 4.5.1) do recognize GCC's __restrict. */
 #define restrict __restrict
-/* KDevelop won't see the ALIGN macro from config.h when viewing files that
- * don't include it directly (e.g. headers). */
-#ifndef ALIGN
-#define ALIGN(x)
-#endif
 #endif
 
 
@@ -682,11 +677,11 @@ struct ALCdevice_struct
     ALuint SamplesDone;
 
     /* Temp storage used for mixing. */
-    ALIGN(16) ALfloat SampleData1[BUFFERSIZE];
-    ALIGN(16) ALfloat SampleData2[BUFFERSIZE];
+    alignas(16) ALfloat SampleData1[BUFFERSIZE];
+    alignas(16) ALfloat SampleData2[BUFFERSIZE];
 
     // Dry path buffer mix
-    ALIGN(16) ALfloat DryBuffer[MaxChannels][BUFFERSIZE];
+    alignas(16) ALfloat DryBuffer[MaxChannels][BUFFERSIZE];
 
     /* Running count of the mixer invocations, in 31.1 fixed point. This
      * actually increments *twice* when mixing, first at the start and then at
@@ -708,7 +703,7 @@ struct ALCdevice_struct
     ALCdevice *volatile next;
 
     /* Memory space used by the default slot (Playback devices only) */
-    ALIGN(16) ALCbyte _slot_mem[];
+    alignas(16) ALCbyte _slot_mem[];
 };
 
 // Frequency was requested by the app or config file
@@ -779,7 +774,7 @@ struct ALCcontext_struct
     ALCcontext *volatile next;
 
     /* Memory space used by the listener */
-    ALIGN(16) ALCbyte _listener_mem[];
+    alignas(16) ALCbyte _listener_mem[];
 };
 
 ALCcontext *GetContextRef(void);

OpenAL32/Include/alu.h

@@ -13,7 +13,9 @@
 #include "alMain.h"
 #include "alBuffer.h"
 #include "alFilter.h"
+
 #include "hrtf.h"
+#include "align.h"
 
 
 #define F_PI    (3.14159265358979323846f)
@@ -38,15 +40,15 @@ extern "C" {
 #endif
 
 typedef struct HrtfState {
-    ALIGN(16) ALfloat History[MAX_INPUT_CHANNELS][SRC_HISTORY_LENGTH];
-    ALIGN(16) ALfloat Values[MAX_INPUT_CHANNELS][HRIR_LENGTH][2];
+    alignas(16) ALfloat History[MAX_INPUT_CHANNELS][SRC_HISTORY_LENGTH];
+    alignas(16) ALfloat Values[MAX_INPUT_CHANNELS][HRIR_LENGTH][2];
 } HrtfState;
 
 typedef struct HrtfParams {
     ALfloat Gain;
     ALfloat Dir[3];
-    ALIGN(16) ALfloat Coeffs[MAX_INPUT_CHANNELS][HRIR_LENGTH][2];
-    ALIGN(16) ALfloat CoeffStep[MAX_INPUT_CHANNELS][HRIR_LENGTH][2];
+    alignas(16) ALfloat Coeffs[MAX_INPUT_CHANNELS][HRIR_LENGTH][2];
+    alignas(16) ALfloat CoeffStep[MAX_INPUT_CHANNELS][HRIR_LENGTH][2];
     ALuint Delay[MAX_INPUT_CHANNELS][2];
     ALint DelayStep[MAX_INPUT_CHANNELS][2];
     ALuint IrSize;

config.h.in

@@ -95,6 +95,9 @@
 /* Define if we have C11 _Static_assert support */
 #cmakedefine HAVE_C11_STATIC_ASSERT
 
+/* Define if we have C11 _Alignas support */
+#cmakedefine HAVE_C11_ALIGNAS
+
 /* Define if we have GCC's destructor attribute */
 #cmakedefine HAVE_GCC_DESTRUCTOR
 
@@ -104,6 +107,9 @@
 /* Define if we have stdint.h */
 #cmakedefine HAVE_STDINT_H
 
+/* Define if we have stdalign.h */
+#cmakedefine HAVE_STDALIGN_H
+
 /* Define if we have windows.h */
 #cmakedefine HAVE_WINDOWS_H