1 files changed, 16 insertions, 14 deletions
diff --git a/contrib/libf2c/libF77/pow_zz.c b/contrib/libf2c/libF77/pow_zz.c
index 20faf29..d5cfbf3 100644
--- a/contrib/libf2c/libF77/pow_zz.c
+++ b/contrib/libf2c/libF77/pow_zz.c
@@ -1,23 +1,25 @@
 #include "f2c.h"
 
-#ifdef KR_headers
-double log(), exp(), cos(), sin(), atan2(), f__cabs();
-VOID pow_zz(r,a,b) doublecomplex *r, *a, *b;
-#else
 #undef abs
 #include <math.h>
-extern double f__cabs(double,double);
-void pow_zz(doublecomplex *r, doublecomplex *a, doublecomplex *b)
-#endif
+extern double f__cabs (double, double);
+void
+pow_zz (doublecomplex * r, doublecomplex * a, doublecomplex * b)
 {
-double logr, logi, x, y;
+  double logr, logi, x, y;
 
-logr = log( f__cabs(a->r, a->i) );
-logi = atan2(a->i, a->r);
+  if (a->r == 0.0 && a->i == 0.0)
+    {
+	/* Algorithm below doesn't cope.  */
+        r->r = r->i = 0.0;
+        return;
+    }
+  logr = log (f__cabs (a->r, a->i));
+  logi = atan2 (a->i, a->r);
 
-x = exp( logr * b->r - logi * b->i );
-y = logr * b->i + logi * b->r;
+  x = exp (logr * b->r - logi * b->i);
+  y = logr * b->i + logi * b->r;
 
-r->r = x * cos(y);
-r->i = x * sin(y);
+  r->r = x * cos (y);
+  r->i = x * sin (y);
 }