IOS XIOBASE与XOLCUM问题求助：自定义internal宏冲突排查

我开发贪吃蛇游戏时，在utils文件中写了以下代码：

typedef char s8;
typedef unsigned char u8;
typedef short s16;
typedef unsigned short u16;
typedef int s32;
typedef unsigned int u32;
typedef long long s64;
typedef unsigned long long u64;

#define global_variable static
#define internal static

inline int
clamp(int min, int val, int max) {
    if (val < min) return min;
    if (val > max) return max;
    return val;
}

目前在iOS平台遇到了XIOBASE和XOLCUM相关的编译问题，我怀疑是internal宏引发的命名冲突，但移除该宏直接替换为static后，问题仍然存在。

以下是XIOBASE中的相关代码片段：

template <class _Dummy>
class _Iosb { // define templatized bitmask/enumerated types, instantiate on demand
public:
    enum _Fmtflags { // constants for formatting options
        _Fmtmask = 0xffff,
        _Fmtzero = 0
    };

    static constexpr int skipws     = 0x0001;
    static constexpr int unitbuf    = 0x0002;
    static constexpr int uppercase  = 0x0004;
    static constexpr int showbase   = 0x0008;
    static constexpr int showpoint  = 0x0010;
    static constexpr int showpos    = 0x0020;
    static constexpr int left       = 0x0040;
    static constexpr int right      = 0x0080;
    static constexpr int internal   = 0x0100;
    static constexpr int dec        = 0x0200;
    static constexpr int oct        = 0x0400;
    static constexpr int hex        = 0x0800;
    static constexpr int scientific = 0x1000;
    static constexpr int fixed      = 0x2000;

    static constexpr int hexfloat = 0x3000; // TRANSITION, ABI, GH-3296

    static constexpr int boolalpha   = 0x4000;
    static constexpr int adjustfield = left | right | internal;
    static constexpr int basefield   = dec | oct | hex;
    static constexpr int floatfield  = scientific | fixed;

内容的提问来源于stack exchange，提问作者1fabian4