Make improvements

- Introduce portable sched_getcpu() api
- Support GCC's __target_clones__ feature
- Make fma() go faster on x86 in default mode
- Remove some asan checks from core libraries
- WinMain() now ensures $HOME and $USER are defined

libc/stdbool.h

@@ -2,15 +2,22 @@
 #define COSMOPOLITAN_LIBC_STDBOOL_H_
 
 #ifndef __cplusplus
-#if __STDC_VERSION__ + 0 >= 201112
+
 #define bool _Bool
+#if defined(__STDC_VERSION__) && __STDC_VERSION__ > 201710L
+#define true  ((_Bool) + 1u)
+#define false ((_Bool) + 0u)
 #else
-#define bool unsigned char
-#endif
-#define true 1
+#define true  1
 #define false 0
+#endif
+
+#else /* __cplusplus */
+
+#define _Bool bool
+
 #endif /* __cplusplus */
 
-#define __bool_true_false_are_defined
+#define __bool_true_false_are_defined 1
 
 #endif /* COSMOPOLITAN_LIBC_STDBOOL_H_ */