It seems alignas() is C11 and raylib is C99, so not fully supported #5312

Added a workaround but it has other probably undesired implications

Author: raysan5

src/external/rlsw.h

@@ -610,11 +610,19 @@ SWAPI void swBindTexture(uint32_t id);
 #define RLSW_IMPLEMENTATION
 #if defined(RLSW_IMPLEMENTATION)
 
-#include <stdalign.h>
 #include <stdlib.h>
 #include <stddef.h>
 #include <math.h>           // Required for: floorf(), fabsf()
 
+#if defined(_MSC_VER)
+    #define ALIGNAS(x) __declspec(align(x))
+#elif defined(__GNUC__) || defined(__clang__)
+    #define ALIGNAS(x) __attribute__((aligned(x)))
+#else
+    #include <stdalign.h>
+    #define ALIGNAS(x) alignas(x)
+#endif
+
 #if defined(__FMA__) && defined(__AVX2__)
     #define SW_HAS_FMA_AVX2
     #include <immintrin.h>
@@ -687,8 +695,8 @@ SWAPI void swBindTexture(uint32_t id);
 #define SW_DEG2RAD  (SW_PI/180.0f)
 #define SW_RAD2DEG  (180.0f/SW_PI)
 
-#define SW_COLOR_PIXEL_SIZE     (SW_COLOR_BUFFER_BITS/8)
-#define SW_DEPTH_PIXEL_SIZE     (SW_DEPTH_BUFFER_BITS/8)
+#define SW_COLOR_PIXEL_SIZE     4  //(SW_COLOR_BUFFER_BITS >> 3)
+#define SW_DEPTH_PIXEL_SIZE     (SW_DEPTH_BUFFER_BITS >> 3)
 
 #if (SW_COLOR_BUFFER_BITS == 8)
     #define SW_COLOR_TYPE uint8_t
@@ -817,14 +825,15 @@ typedef struct {
     float ty;                   // Texel height
 } sw_texture_t;
 
-typedef struct {
-    alignas(SW_COLOR_PIXEL_SIZE)
+// Pixel data type
+// WARNING: ALIGNAS() macro requires a constant value (not operand)
+typedef ALIGNAS(SW_COLOR_PIXEL_SIZE) struct {
     SW_COLOR_TYPE color[SW_COLOR_PACK_COMP];
     SW_DEPTH_TYPE depth[SW_DEPTH_PACK_COMP];
 } sw_pixel_t;
 
 typedef struct {
-    sw_pixel_t* pixels;
+    sw_pixel_t *pixels;
     int width;
     int height;
     int allocSz;