Take upstream libm changes.

Mostly workarounds for GCC and Clang bugs.

Change-Id: I4ef428a42d4ac6d622659053711a8cc416925727
diff --git a/libm/upstream-freebsd/lib/msun/src/e_exp.c b/libm/upstream-freebsd/lib/msun/src/e_exp.c
index e432bc8..94c9769 100644
--- a/libm/upstream-freebsd/lib/msun/src/e_exp.c
+++ b/libm/upstream-freebsd/lib/msun/src/e_exp.c
@@ -84,7 +84,6 @@
 static const double
 one	= 1.0,
 halF[2]	= {0.5,-0.5,},
-huge	= 1.0e+300,
 o_threshold=  7.09782712893383973096e+02,  /* 0x40862E42, 0xFEFA39EF */
 u_threshold= -7.45133219101941108420e+02,  /* 0xc0874910, 0xD52D3051 */
 ln2HI[2]   ={ 6.93147180369123816490e-01,  /* 0x3fe62e42, 0xfee00000 */
@@ -99,6 +98,7 @@
 P5   =  4.13813679705723846039e-08; /* 0x3E663769, 0x72BEA4D0 */
 
 static volatile double
+huge	= 1.0e+300,
 twom1000= 9.33263618503218878990e-302;     /* 2**-1000=0x01700000,0*/
 
 double