From 60e235ee2ae834bb9f7a884f1b192304b9fdcf33 Mon Sep 17 00:00:00 2001
From: Joseph Myers <joseph@codesourcery.com>
Date: Wed, 7 Nov 2012 13:03:31 +0000
Subject: Fix spurious underflows from pow with results close to 1 (bug 14811).

---
 sysdeps/ieee754/flt-32/e_powf.c | 4 ++++
 1 file changed, 4 insertions(+)

(limited to 'sysdeps/ieee754/flt-32/e_powf.c')

diff --git a/sysdeps/ieee754/flt-32/e_powf.c b/sysdeps/ieee754/flt-32/e_powf.c
index 43069479a5..12c408f93c 100644
--- a/sysdeps/ieee754/flt-32/e_powf.c
+++ b/sysdeps/ieee754/flt-32/e_powf.c
@@ -141,6 +141,10 @@ __ieee754_powf(float x, float y)
 	    t2 = v-(t1-u);
 	} else {
 	    float s2,s_h,s_l,t_h,t_l;
+	    /* Avoid internal underflow for tiny y.  The exact value
+	       of y does not matter if |y| <= 2**-32.  */
+	    if (iy < 0x2f800000)
+	      SET_FLOAT_WORD (y, (hy & 0x80000000) | 0x2f800000);
 	    n = 0;
 	/* take care subnormal number */
 	    if(ix<0x00800000)
-- 
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