external指针外部RAM中的数据作为函数参数传递得到XC16编译器错误

我用完了我的PIC24的内部RAM，认为我很聪明，把一些大的结构移到外部的SPI RAM芯片上。我编写了TythAuxRead Sub（）和AuthOrthRead Enter（）RAM驱动函数，它工作得很好。但是当我把指针指向这些结构到其他代码时，我得到XC16编译器错误，例如：“错误：从指针到非封闭地址空间的‘STLLN’传递参数1”。（已经编译的）SrLLN（CHAR*STR）的库代码不具有用于外部引用的胶粘代码。好的。但是，我是否需要对我当前的所有源代码进行新的版本，这样它也可以不包括外加指针？例如，MyStReGrimeCar（char * a，char *b）需要生成4种不同的调用签名来处理所有可能的场景：MyStRestCopReRe1（SuthalLax.char *a，char *b）MyStRePrimCARCAR2（char *a，yxAuthalLuxchar *b）MyStrugCoprRe3（SuthalAlxa char * a，yxEnthalLuxchar *b）MyStrugCoprRe4（char *）A、Char * B）有人建议我如何在不复制大量代码的情况下做到这一点？XC16能在后台自动地实现这一点吗？就像一个编译器选项：“自动生成方法在传递‘外外部指针’时的变体”，或者我可以声明这些函数是接受外部的指针，它们还会用正常的指针工作吗？也许会罚点球。



      以下为原文

    I ran out of internal RAM of my PIC24 and thought I would be smart and move some large structures out to the external SPI RAM chips. I wrote the __read_external() and __write_external() ram driver functions and that works fine.
But when I pass pointers to these structures to other code I get xc16 compiler errors such as:
"error: passing argument 1 of 'strlen' from pointer to non-enclosed address space"

I'm assuming it means that the (already compiled) library code for strlen(char* str) doesn't have the glue code to derference an external pointeral.  Fine. But do I need to make new versions of the functions of all my current source code so it can also except __extern__ pointers?
E.g  myStringCompare(char* a, char* b)  would need to make 4 different call signatures to handle all possible scenarios:
myStringCompare1( __external__ char* a, char* b)
myStringCompare2( char* a, __external__ char* b)
myStringCompare3( __external__ char* a, __external__ char* b)
myStringCompare4( char* a, char* b)

Anyone has advice how I can do this without duplicating a lot of code?

Could the xc16 make this automagically in the background? Like a compiler option:
"Auto generate method variants when passing __external__ pointers"

Or could I declare the functions as accepting __external__ pointers and they would still work also with normal pointers?
Maybe with some speed penalty.