Use STRICT_ASSIGN() to ensure that the compiler doesn't screw things

up by storing x in a wider type than it's supposed to.

Submitted by:	bde

4 files changed, 13 insertions, 5 deletions

diff --git a/lib/msun/src/e_exp.c b/lib/msun/src/e_exp.c
index 5b9a10c1a3d6..b47aef583c98 100644
--- a/lib/msun/src/e_exp.c
+++ b/lib/msun/src/e_exp.c
@@ -76,6 +76,8 @@ __FBSDID("$FreeBSD$");
  * to produce the hexadecimal values shown.
  */
 
+#include <float.h>
+
 #include "math.h"
 #include "math_private.h"
 
@@ -133,7 +135,7 @@ __ieee754_exp(double x)	/* default IEEE double exp */
 		hi = x - t*ln2HI[0];	/* t*ln2HI is exact here */
 		lo = t*ln2LO[0];
 	    }
-	    x  = hi - lo;
+	    STRICT_ASSIGN(double, x, hi - lo);
 	} 
 	else if(hx < 0x3e300000)  {	/* when |x|<2**-28 */
 	    if(huge+x>one) return one+x;/* trigger inexact */
diff --git a/lib/msun/src/e_expf.c b/lib/msun/src/e_expf.c
index 502e42138d11..a4790765bcb5 100644
--- a/lib/msun/src/e_expf.c
+++ b/lib/msun/src/e_expf.c
@@ -16,6 +16,8 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include <float.h>
+
 #include "math.h"
 #include "math_private.h"
 
@@ -40,7 +42,7 @@ P2 = -2.7667332906e-3;		/* -0xb55215.0p-32 */
 static volatile float twom100 = 7.8886090522e-31;      /* 2**-100=0x0d800000 */
 
 float
-__ieee754_expf(float x)	/* default IEEE double exp */
+__ieee754_expf(float x)
 {
 	float y,hi=0.0,lo=0.0,c,t,twopk;
 	int32_t k=0,xsb;
@@ -70,7 +72,7 @@ __ieee754_expf(float x)	/* default IEEE double exp */
 		hi = x - t*ln2HI[0];	/* t*ln2HI is exact here */
 		lo = t*ln2LO[0];
 	    }
-	    x  = hi - lo;
+	    STRICT_ASSIGN(float, x, hi - lo);
 	}
 	else if(hx < 0x39000000)  {	/* when |x|<2**-14 */
 	    if(huge+x>one) return one+x;/* trigger inexact */
diff --git a/lib/msun/src/s_expm1.c b/lib/msun/src/s_expm1.c
index f41c7e3e99c6..5aa1917b5a4c 100644
--- a/lib/msun/src/s_expm1.c
+++ b/lib/msun/src/s_expm1.c
@@ -108,6 +108,8 @@ __FBSDID("$FreeBSD$");
  * to produce the hexadecimal values shown.
  */
 
+#include <float.h>
+
 #include "math.h"
 #include "math_private.h"
 
@@ -168,7 +170,7 @@ expm1(double x)
 		hi = x - t*ln2_hi;	/* t*ln2_hi is exact here */
 		lo = t*ln2_lo;
 	    }
-	    x  = hi - lo;
+	    STRICT_ASSIGN(double, x, hi - lo);
 	    c  = (hi-x)-lo;
 	}
 	else if(hx < 0x3c900000) {  	/* when |x|<2**-54, return x */
diff --git a/lib/msun/src/s_expm1f.c b/lib/msun/src/s_expm1f.c
index d7dd1b90c464..fb374943000e 100644
--- a/lib/msun/src/s_expm1f.c
+++ b/lib/msun/src/s_expm1f.c
@@ -16,6 +16,8 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include <float.h>
+
 #include "math.h"
 #include "math_private.h"
 
@@ -74,7 +76,7 @@ expm1f(float x)
 		hi = x - t*ln2_hi;	/* t*ln2_hi is exact here */
 		lo = t*ln2_lo;
 	    }
-	    x  = hi - lo;
+	    STRICT_ASSIGN(float, x, hi - lo);
 	    c  = (hi-x)-lo;
 	}
 	else if(hx < 0x33000000) {  	/* when |x|<2**-25, return x */