在Shewchuk的Triangle程序上编译OSX上的C浮点运算

Question

This question suggests that the best way to triangulate a polygon with holes is to use Shewchuk's Triangle library , but I'm having trouble getting it to compile on my mac OSX. It is a very popular program that has been around for a while, and therefore should be relatively easy to compile, I'm just inexperienced with C.

This is the error I'm getting:

$ make
cc -O -DLINUX -I/usr/X11R6/include -L/usr/X11R6/lib -o ./triangle ./triangle.c -lm
Undefined symbols:
  "__FPU_SETCW", referenced from:
   _exactinit in ccrEJvxc.o
ld: symbol(s) not found
collect2: ld returned 1 exit status
make: *** [triangle] Error 1

I'm trying to comment out certain flags (ie #define LINUX , etc.) but I get a different set of errors for each combination.

Could someone walk me through step-by-step how to compile (and possibly call) this program on a mac?

Answer 1

我设法通过从makefile中的CSWITCHES定义中删除-DLINUX标志来编译OS X，因为fpu_control.h似乎是特定于linux的。

Answer 2

I don't believe that's a standard function and in any case I believe the Mac .. whose use of the Intel architecture post-dates SSE .. never had a reason to support 387-style FPU ops.

So your code is Linux-specific. You can either remove the linux specific code or implement do-nothing versions of its entry points.

I wouldn't do this myself, but you might get away with:

$ cat > /usr/include/fpu_control.h

#define _FPU_SETCW(cw) // nothing
#define _FPU_GETCW(cw) // nothing

Don't worry about the null implementations. You don't need to tweak the FPU exception and rounding modes.