JavaScriptCore console.log

I've put together a very simple program that uses JavaScriptCore to evaluate JS:

#import <CoreFoundation/CoreFoundation.h>
#import <JavaScriptCore/JavaScriptCore.h>

int main(int argc, const char * argv[])
{
    JSGlobalContextRef ctx = JSGlobalContextCreate(NULL);

    FILE *f = fopen(argv[1],"r");
    char * buffer = malloc(10000000);
    fread(buffer,1,10000000,f);

    CFStringRef strs = CFStringCreateWithCString(NULL, buffer, kCFStringEncodingASCII);

    JSStringRef jsstr = JSStringCreateWithCFString(strs);
    JSValueRef result = JSEvaluateScript(ctx, jsstr, NULL, NULL, 0, NULL);

    double res  = JSValueToNumber(ctx, result, NULL);
    JSGlobalContextRelease(ctx);

    printf("%lf\n", res);
    return 0;
}

The idea here is that the last value is expected to be a Number, and that value is printed. This works for valid javascript code, such as

var square = function(x) { return x*x; }; square(4)

However, if the code tries to perform a console.log, the program segfaults. Is there a log function available in JSC or do I have to roll my own?

from JavaScriptCore console.log