fixing minor bugs with single unit compilation in gcc with flags on

kernel/types.h

@@ -0,0 +1,62 @@
+#ifndef TYPES_H
+#define TYPES_H
+
+// ----------------------------
+// Fixed-width integer types
+// ----------------------------
+typedef unsigned char      uint8_t;
+typedef signed char        int8_t;
+typedef unsigned short     uint16_t;
+typedef signed short       int16_t;
+typedef unsigned int       uint32_t;
+typedef signed int         int32_t;
+typedef unsigned long long uint64_t;
+typedef signed long long   int64_t;
+
+// ----------------------------
+// Boolean & NULL definitions
+// ----------------------------
+#ifndef __cplusplus
+typedef enum { false = 0, true = 1 } bool;
+#endif
+
+#ifndef NULL
+#define NULL ((void*)0)
+#endif
+
+// ----------------------------
+// OS subsystem types
+// ----------------------------
+typedef uint32_t size_t;
+typedef int32_t  ssize_t;
+
+typedef uint32_t phys_addr_t; // Physical address
+typedef uint32_t virt_addr_t; // Virtual address
+
+typedef uint32_t pid_t;       // Process ID
+typedef uint32_t tid_t;       // Thread ID
+
+// ----------------------------
+// Bitfield & utility macros
+// ----------------------------
+#define BIT(n) (1U << (n))
+#define BITS(m, n) (((1U << ((n) - (m) + 1)) - 1) << (m))
+
+// Align value to next multiple of alignment
+#define ALIGN_UP(val, align) (((val) + ((align)-1)) & ~((align)-1))
+#define ALIGN_DOWN(val, align) ((val) & ~((align)-1))
+
+// ----------------------------
+// Attributes for structures
+// ----------------------------
+#define PACKED      __attribute__((packed))
+#define ALIGN(x)    __attribute__((aligned(x)))
+
+// ----------------------------
+// Likely/unlikely branch hints
+// (for future optimization use)
+// ----------------------------
+#define likely(x)   __builtin_expect(!!(x), 1)
+#define unlikely(x) __builtin_expect(!!(x), 0)
+
+#endif // TYPES_H