The following simple example shows how/why buildworld for lib32 on powerpc64 fails to compile libedit.

lang/gcc49, lang/gcc5, and devel/powerpc64-gcc all fail to compile the following "main.c" for -m32 on powerpc64.

#include "/usr/include/stddef.h"

const wchar_t* test(const wchar_t* p) { return p; }

int main(void)
{
    const wchar_t* wcpt      = test(L"test");
    const wchar_t  wcarray[] = L"test";
    return 0;
}

For "gcc49 -m32 main.c" the result is:

# gcc49 -m32 main.c
main.c: In function 'main':
main.c:7:37: warning: passing argument 1 of 'test' from incompatible pointer type
     const wchar_t* wcpt      = test(L"test");
                                     ^
main.c:3:16: note: expected 'const wchar_t *' but argument is of type 'long int *'
 const wchar_t* test(const wchar_t* p) { return p; }
                ^
main.c:8:5: error: array of inappropriate type initialized from string constant
     const wchar_t  wcarray[] = L"test";
     ^

gcc5 and powerpc64-gcc get the same.

A possible fix via an addition to lang/gcc5's and devel/powerpc64-gcc's patch-gcc-freebsd-powerpc64 would look like (tabs likely not preserved):

+@@ -304,7 +317,7 @@
+ 
+ /* rs6000.h gets this wrong for FreeBSD.  We use the GCC defaults instead.  */
+ #undef WCHAR_TYPE
+-#define	WCHAR_TYPE      (TARGET_64BIT ? "int" : "long int")
++#define	WCHAR_TYPE      "int"
+ #undef  WCHAR_TYPE_SIZE
+ #define WCHAR_TYPE_SIZE 32
+ 

It appears that lang/gcc49, lang/gcc5-devel, and lang/gcc6-devel do not have a patch-gcc-freebsd-powerpc64 (yet?). Nor lang/gcc48 or older. At least for gcc49 the content of a patch for this issue could be similar from what I can see. I've not looked at the details for the others.

Note: FreeBSD for powerpc64 and its lib32 context define ___wchar_t as int:

# grep wchar_t /usr/include/machine/_types.h                                                                                                                                             typedef	int		___wchar_t;
#define	__WCHAR_MIN	__INT_MIN	/* min value for a wchar_t */
#define	__WCHAR_MAX	__INT_MAX	/* max value for a wchar_t */