diff --git a/src/eval.c b/src/eval.c
index 9d2c5ac..70fbc88 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -5971,6 +5971,22 @@
     char	*s = (char *)text;
     float_T	f;
 
+    /* MS-Windows does not deal with "inf" and "nan" properly. */
+    if (STRNICMP(text, "inf", 3) == 0)
+    {
+	*value = INFINITY;
+	return 3;
+    }
+    if (STRNICMP(text, "-inf", 3) == 0)
+    {
+	*value = -INFINITY;
+	return 4;
+    }
+    if (STRNICMP(text, "nan", 3) == 0)
+    {
+	*value = NAN;
+	return 3;
+    }
     f = strtod(s, &s);
     *value = f;
     return (int)((char_u *)s - text);
diff --git a/src/testdir/test_float_func.vim b/src/testdir/test_float_func.vim
index 25633d9..e51b83e 100644
--- a/src/testdir/test_float_func.vim
+++ b/src/testdir/test_float_func.vim
@@ -5,223 +5,227 @@
 end
 
 func Test_abs()
-  call assert_equal(string(abs(1.23)), '1.23')
-  call assert_equal(string(abs(-1.23)), '1.23')
-  call assert_equal(string(abs(0.0)), '0.0')
-  call assert_equal(string(abs(1.0/(1.0/0.0))), '0.0')
-  call assert_equal(string(abs(-1.0/(1.0/0.0))), '0.0')
-  call assert_equal(string(abs(1.0/0.0)), 'inf')
-  call assert_equal(string(abs(-1.0/0.0)), 'inf')
-  call assert_equal(string(abs(0.0/0.0)), 'nan')
+  call assert_equal('1.23', string(abs(1.23)))
+  call assert_equal('1.23', string(abs(-1.23)))
+  call assert_equal('0.0', string(abs(0.0)))
+  call assert_equal('0.0', string(abs(1.0/(1.0/0.0))))
+  call assert_equal('0.0', string(abs(-1.0/(1.0/0.0))))
+  call assert_equal('inf', string(abs(1.0/0.0)))
+  call assert_equal('inf', string(abs(-1.0/0.0)))
+  call assert_equal('nan', string(abs(0.0/0.0)))
 endfunc
 
 func Test_sqrt()
-  call assert_equal(string(sqrt(0.0)), '0.0')
-  call assert_equal(string(sqrt(2.0)), '1.414214')
-  call assert_equal(string(sqrt(1.0/0.0)), 'inf')
-  call assert_equal(string(sqrt(-1.0)), 'nan')
-  call assert_equal(string(sqrt(0.0/0.0)), 'nan')
+  call assert_equal('0.0', string(sqrt(0.0)))
+  call assert_equal('1.414214', string(sqrt(2.0)))
+  call assert_equal('inf', string(sqrt(1.0/0.0)))
+  call assert_equal('nan', string(sqrt(-1.0)))
+  call assert_equal('nan', string(sqrt(0.0/0.0)))
 endfunc
 
 func Test_log()
-  call assert_equal(string(log(1.0)), '0.0')
-  call assert_equal(string(log(0.5)), '-0.693147')
-  call assert_equal(string(log(0.0)), '-inf')
-  call assert_equal(string(log(-1.0)), 'nan')
-  call assert_equal(string(log(1.0/0.0)), 'inf')
-  call assert_equal(string(log(0.0/0.0)), 'nan')
+  call assert_equal('0.0', string(log(1.0)))
+  call assert_equal('-0.693147', string(log(0.5)))
+  call assert_equal('-inf', string(log(0.0)))
+  call assert_equal('nan', string(log(-1.0)))
+  call assert_equal('inf', string(log(1.0/0.0)))
+  call assert_equal('nan', string(log(0.0/0.0)))
 endfunc
 
 func Test_log10()
-  call assert_equal(string(log10(1.0)), '0.0')
-  call assert_equal(string(log10(100.0)), '2.0')
-  call assert_equal(string(log10(120.0)), '2.079181')
-  call assert_equal(string(log10(0.0)), '-inf')
-  call assert_equal(string(log10(-1.0)), 'nan')
-  call assert_equal(string(log10(1.0/0.0)), 'inf')
-  call assert_equal(string(log10(0.0/0.0)), 'nan')
+  call assert_equal('0.0', string(log10(1.0)))
+  call assert_equal('2.0', string(log10(100.0)))
+  call assert_equal('2.079181', string(log10(120.0)))
+  call assert_equal('-inf', string(log10(0.0)))
+  call assert_equal('nan', string(log10(-1.0)))
+  call assert_equal('inf', string(log10(1.0/0.0)))
+  call assert_equal('nan', string(log10(0.0/0.0)))
 endfunc
 
 func Test_exp()
-  call assert_equal(string(exp(0.0)), '1.0')
-  call assert_equal(string(exp(2.0)), '7.389056')
-  call assert_equal(string(exp(-1.0)),'0.367879')
-  call assert_equal(string(exp(1.0/0.0)), 'inf')
-  call assert_equal(string(exp(-1.0/0.0)), '0.0')
-  call assert_equal(string(exp(0.0/0.0)), 'nan')
+  call assert_equal('1.0', string(exp(0.0)))
+  call assert_equal('7.389056', string(exp(2.0)))
+  call assert_equal('0.367879', string(exp(-1.0)))
+  call assert_equal('inf', string(exp(1.0/0.0)))
+  call assert_equal('0.0', string(exp(-1.0/0.0)))
+  call assert_equal('nan', string(exp(0.0/0.0)))
 endfunc
 
 func Test_sin()
-  call assert_equal(string(sin(0.0)), '0.0')
-  call assert_equal(string(sin(1.0)), '0.841471')
-  call assert_equal(string(sin(-0.5)), '-0.479426')
-  call assert_equal(string(sin(0.0/0.0)), 'nan')
-  call assert_equal(string(sin(1.0/0.0)), 'nan')
-  call assert_equal(string(sin(1.0/(1.0/0.0))), '0.0')
-  call assert_equal(string(sin(-1.0/(1.0/0.0))), '-0.0')
+  call assert_equal('0.0', string(sin(0.0)))
+  call assert_equal('0.841471', string(sin(1.0)))
+  call assert_equal('-0.479426', string(sin(-0.5)))
+  call assert_equal('nan', string(sin(0.0/0.0)))
+  call assert_equal('nan', string(sin(1.0/0.0)))
+  call assert_equal('0.0', string(sin(1.0/(1.0/0.0))))
+  call assert_equal('-0.0', string(sin(-1.0/(1.0/0.0))))
 endfunc
 
 func Test_asin()
-  call assert_equal(string(asin(0.0)), '0.0')
-  call assert_equal(string(asin(1.0)), '1.570796')
-  call assert_equal(string(asin(-0.5)), '-0.523599')
-  call assert_equal(string(asin(1.1)), 'nan')
-  call assert_equal(string(asin(1.0/0.0)), 'nan')
-  call assert_equal(string(asin(0.0/0.0)), 'nan')
+  call assert_equal('0.0', string(asin(0.0)))
+  call assert_equal('1.570796', string(asin(1.0)))
+  call assert_equal('-0.523599', string(asin(-0.5)))
+  call assert_equal('nan', string(asin(1.1)))
+  call assert_equal('nan', string(asin(1.0/0.0)))
+  call assert_equal('nan', string(asin(0.0/0.0)))
 endfunc
 
 func Test_sinh()
-  call assert_equal(string(sinh(0.0)), '0.0')
-  call assert_equal(string(sinh(0.5)), '0.521095')
-  call assert_equal(string(sinh(-0.9)), '-1.026517')
-  call assert_equal(string(sinh(1.0/0.0)), 'inf')
-  call assert_equal(string(sinh(-1.0/0.0)), '-inf')
-  call assert_equal(string(sinh(0.0/0.0)), 'nan')
+  call assert_equal('0.0', string(sinh(0.0)))
+  call assert_equal('0.521095', string(sinh(0.5)))
+  call assert_equal('-1.026517', string(sinh(-0.9)))
+  call assert_equal('inf', string(sinh(1.0/0.0)))
+  call assert_equal('-inf', string(sinh(-1.0/0.0)))
+  call assert_equal('nan', string(sinh(0.0/0.0)))
 endfunc
 
 func Test_cos()
-  call assert_equal(string(cos(0.0)), '1.0')
-  call assert_equal(string(cos(1.0)), '0.540302')
-  call assert_equal(string(cos(-0.5)), '0.877583')
-  call assert_equal(string(cos(0.0/0.0)), 'nan')
-  call assert_equal(string(cos(1.0/0.0)), 'nan')
+  call assert_equal('1.0', string(cos(0.0)))
+  call assert_equal('0.540302', string(cos(1.0)))
+  call assert_equal('0.877583', string(cos(-0.5)))
+  call assert_equal('nan', string(cos(0.0/0.0)))
+  call assert_equal('nan', string(cos(1.0/0.0)))
 endfunc
 
 func Test_acos()
-  call assert_equal(string(acos(0.0)), '1.570796')
-  call assert_equal(string(acos(1.0)), '0.0')
-  call assert_equal(string(acos(-1.0)), '3.141593')
-  call assert_equal(string(acos(-0.5)), '2.094395')
-  call assert_equal(string(acos(1.1)), 'nan')
-  call assert_equal(string(acos(1.0/0.0)), 'nan')
-  call assert_equal(string(acos(0.0/0.0)), 'nan')
+  call assert_equal('1.570796', string(acos(0.0)))
+  call assert_equal('0.0', string(acos(1.0)))
+  call assert_equal('3.141593', string(acos(-1.0)))
+  call assert_equal('2.094395', string(acos(-0.5)))
+  call assert_equal('nan', string(acos(1.1)))
+  call assert_equal('nan', string(acos(1.0/0.0)))
+  call assert_equal('nan', string(acos(0.0/0.0)))
 endfunc
 
 func Test_cosh()
-  call assert_equal(string(cosh(0.0)), '1.0')
-  call assert_equal(string(cosh(0.5)), '1.127626')
-  call assert_equal(string(cosh(1.0/0.0)), 'inf')
-  call assert_equal(string(cosh(-1.0/0.0)), 'inf')
-  call assert_equal(string(cosh(0.0/0.0)), 'nan')
+  call assert_equal('1.0', string(cosh(0.0)))
+  call assert_equal('1.127626', string(cosh(0.5)))
+  call assert_equal('inf', string(cosh(1.0/0.0)))
+  call assert_equal('inf', string(cosh(-1.0/0.0)))
+  call assert_equal('nan', string(cosh(0.0/0.0)))
 endfunc
 
 func Test_tan()
-  call assert_equal(string(tan(0.0)), '0.0')
-  call assert_equal(string(tan(0.5)), '0.546302')
-  call assert_equal(string(tan(-0.5)), '-0.546302')
-  call assert_equal(string(tan(1.0/0.0)), 'nan')
-  call assert_equal(string(cos(0.0/0.0)), 'nan')
-  call assert_equal(string(tan(1.0/(1.0/0.0))), '0.0')
-  call assert_equal(string(tan(-1.0/(1.0/0.0))), '-0.0')
+  call assert_equal('0.0', string(tan(0.0)))
+  call assert_equal('0.546302', string(tan(0.5)))
+  call assert_equal('-0.546302', string(tan(-0.5)))
+  call assert_equal('nan', string(tan(1.0/0.0)))
+  call assert_equal('nan', string(cos(0.0/0.0)))
+  call assert_equal('0.0', string(tan(1.0/(1.0/0.0))))
+  call assert_equal('-0.0', string(tan(-1.0/(1.0/0.0))))
 endfunc
 
 func Test_atan()
-  call assert_equal(string(atan(0.0)), '0.0')
-  call assert_equal(string(atan(0.5)), '0.463648')
-  call assert_equal(string(atan(-1.0)), '-0.785398')
-  call assert_equal(string(atan(1.0/0.0)), '1.570796')
-  call assert_equal(string(atan(-1.0/0.0)), '-1.570796')
-  call assert_equal(string(atan(0.0/0.0)), 'nan')
+  call assert_equal('0.0', string(atan(0.0)))
+  call assert_equal('0.463648', string(atan(0.5)))
+  call assert_equal('-0.785398', string(atan(-1.0)))
+  call assert_equal('1.570796', string(atan(1.0/0.0)))
+  call assert_equal('-1.570796', string(atan(-1.0/0.0)))
+  call assert_equal('nan', string(atan(0.0/0.0)))
 endfunc
 
 func Test_atan2()
-  call assert_equal(string(atan2(-1, -1)), '-2.356194')
-  call assert_equal(string(atan2(1, -1)), '2.356194')
-  call assert_equal(string(atan2(1.0, 1.0/0.0)), '0.0')
-  call assert_equal(string(atan2(1.0/0.0, 1.0)), '1.570796')
-  call assert_equal(string(atan2(0.0/0.0, 1.0)), 'nan')
+  call assert_equal('-2.356194', string(atan2(-1, -1)))
+  call assert_equal('2.356194', string(atan2(1, -1)))
+  call assert_equal('0.0', string(atan2(1.0, 1.0/0.0)))
+  call assert_equal('1.570796', string(atan2(1.0/0.0, 1.0)))
+  call assert_equal('nan', string(atan2(0.0/0.0, 1.0)))
 endfunc
 
 func Test_tanh()
-  call assert_equal(string(tanh(0.0)), '0.0')
-  call assert_equal(string(tanh(0.5)), '0.462117')
-  call assert_equal(string(tanh(-1.0)), '-0.761594')
-  call assert_equal(string(tanh(1.0/0.0)), '1.0')
-  call assert_equal(string(tanh(-1.0/0.0)), '-1.0')
-  call assert_equal(string(tanh(0.0/0.0)), 'nan')
+  call assert_equal('0.0', string(tanh(0.0)))
+  call assert_equal('0.462117', string(tanh(0.5)))
+  call assert_equal('-0.761594', string(tanh(-1.0)))
+  call assert_equal('1.0', string(tanh(1.0/0.0)))
+  call assert_equal('-1.0', string(tanh(-1.0/0.0)))
+  call assert_equal('nan', string(tanh(0.0/0.0)))
 endfunc
 
 func Test_fmod()
-  call assert_equal(string(fmod(12.33, 1.22)), '0.13')
-  call assert_equal(string(fmod(-12.33, 1.22)), '-0.13')
-  call assert_equal(string(fmod(1.0/0.0, 1.0)), 'nan')
-  call assert_equal(string(fmod(1.0, 1.0/0.0)), '1.0')
-  call assert_equal(string(fmod(1.0, 0.0)), 'nan')
+  call assert_equal('0.13', string(fmod(12.33, 1.22)))
+  call assert_equal('-0.13', string(fmod(-12.33, 1.22)))
+  call assert_equal('nan', string(fmod(1.0/0.0, 1.0)))
+  " On Windows we get "nan" instead of 1.0, accept both.
+  let res = string(fmod(1.0, 1.0/0.0))
+  if res != 'nan'
+    call assert_equal('1.0', res)
+  endif
+  call assert_equal('nan', string(fmod(1.0, 0.0)))
 endfunc
 
 func Test_pow()
-  call assert_equal(string(pow(0.0, 0.0)), '1.0')
-  call assert_equal(string(pow(2.0, 3.0)), '8.0')
-  call assert_equal(string(pow(2.0, 0.0/0.0)), 'nan')
-  call assert_equal(string(pow(0.0/0.0, 3.0)), 'nan')
-  call assert_equal(string(pow(0.0/0.0, 3.0)), 'nan')
-  call assert_equal(string(pow(2.0, 1.0/0.0)), 'inf')
-  call assert_equal(string(pow(1.0/0.0, 3.0)), 'inf')
+  call assert_equal('1.0', string(pow(0.0, 0.0)))
+  call assert_equal('8.0', string(pow(2.0, 3.0)))
+  call assert_equal('nan', string(pow(2.0, 0.0/0.0)))
+  call assert_equal('nan', string(pow(0.0/0.0, 3.0)))
+  call assert_equal('nan', string(pow(0.0/0.0, 3.0)))
+  call assert_equal('inf', string(pow(2.0, 1.0/0.0)))
+  call assert_equal('inf', string(pow(1.0/0.0, 3.0)))
 endfunc
 
 func Test_str2float()
-  call assert_equal(string(str2float('1')), '1.0')
-  call assert_equal(string(str2float('1.23')), '1.23')
-  call assert_equal(string(str2float('1.23abc')), '1.23')
-  call assert_equal(string(str2float('1e40')), '1.0e40')
-  call assert_equal(string(str2float('1e1000')), 'inf')
-  call assert_equal(string(str2float('inf')), 'inf')
-  call assert_equal(string(str2float('-inf')), '-inf')
-  call assert_equal(string(str2float('Inf')), 'inf')
-  call assert_equal(string(str2float('nan')), 'nan')
-  call assert_equal(string(str2float('NaN')), 'nan')
+  call assert_equal('1.0', string(str2float('1')))
+  call assert_equal('1.23', string(str2float('1.23')))
+  call assert_equal('1.23', string(str2float('1.23abc')))
+  call assert_equal('1.0e40', string(str2float('1e40')))
+  call assert_equal('inf', string(str2float('1e1000')))
+  call assert_equal('inf', string(str2float('inf')))
+  call assert_equal('-inf', string(str2float('-inf')))
+  call assert_equal('inf', string(str2float('Inf')))
+  call assert_equal('nan', string(str2float('nan')))
+  call assert_equal('nan', string(str2float('NaN')))
 endfunc
 
 func Test_floor()
-  call assert_equal(string(floor(2.0)), '2.0')
-  call assert_equal(string(floor(2.11)), '2.0')
-  call assert_equal(string(floor(2.99)), '2.0')
-  call assert_equal(string(floor(-2.11)), '-3.0')
-  call assert_equal(string(floor(-2.99)), '-3.0')
-  call assert_equal(string(floor(0.0/0.0)), 'nan')
-  call assert_equal(string(floor(1.0/0.0)), 'inf')
-  call assert_equal(string(floor(-1.0/0.0)), '-inf')
+  call assert_equal('2.0', string(floor(2.0)))
+  call assert_equal('2.0', string(floor(2.11)))
+  call assert_equal('2.0', string(floor(2.99)))
+  call assert_equal('-3.0', string(floor(-2.11)))
+  call assert_equal('-3.0', string(floor(-2.99)))
+  call assert_equal('nan', string(floor(0.0/0.0)))
+  call assert_equal('inf', string(floor(1.0/0.0)))
+  call assert_equal('-inf', string(floor(-1.0/0.0)))
 endfunc
 
 func Test_ceil()
-  call assert_equal(string(ceil(2.0)), '2.0')
-  call assert_equal(string(ceil(2.11)), '3.0')
-  call assert_equal(string(ceil(2.99)), '3.0')
-  call assert_equal(string(ceil(-2.11)), '-2.0')
-  call assert_equal(string(ceil(-2.99)), '-2.0')
-  call assert_equal(string(ceil(0.0/0.0)), 'nan')
-  call assert_equal(string(ceil(1.0/0.0)), 'inf')
-  call assert_equal(string(ceil(-1.0/0.0)), '-inf')
+  call assert_equal('2.0', string(ceil(2.0)))
+  call assert_equal('3.0', string(ceil(2.11)))
+  call assert_equal('3.0', string(ceil(2.99)))
+  call assert_equal('-2.0', string(ceil(-2.11)))
+  call assert_equal('-2.0', string(ceil(-2.99)))
+  call assert_equal('nan', string(ceil(0.0/0.0)))
+  call assert_equal('inf', string(ceil(1.0/0.0)))
+  call assert_equal('-inf', string(ceil(-1.0/0.0)))
 endfunc
 
 func Test_round()
-  call assert_equal(string(round(2.1)), '2.0')
-  call assert_equal(string(round(2.5)), '3.0')
-  call assert_equal(string(round(2.9)), '3.0')
-  call assert_equal(string(round(-2.1)), '-2.0')
-  call assert_equal(string(round(-2.5)), '-3.0')
-  call assert_equal(string(round(-2.9)), '-3.0')
-  call assert_equal(string(round(0.0/0.0)), 'nan')
-  call assert_equal(string(round(1.0/0.0)), 'inf')
-  call assert_equal(string(round(-1.0/0.0)), '-inf')
+  call assert_equal('2.0', string(round(2.1)))
+  call assert_equal('3.0', string(round(2.5)))
+  call assert_equal('3.0', string(round(2.9)))
+  call assert_equal('-2.0', string(round(-2.1)))
+  call assert_equal('-3.0', string(round(-2.5)))
+  call assert_equal('-3.0', string(round(-2.9)))
+  call assert_equal('nan', string(round(0.0/0.0)))
+  call assert_equal('inf', string(round(1.0/0.0)))
+  call assert_equal('-inf', string(round(-1.0/0.0)))
 endfunc
 
 func Test_trunc()
-  call assert_equal(string(trunc(2.1)), '2.0')
-  call assert_equal(string(trunc(2.5)), '2.0')
-  call assert_equal(string(trunc(2.9)), '2.0')
-  call assert_equal(string(trunc(-2.1)), '-2.0')
-  call assert_equal(string(trunc(-2.5)), '-2.0')
-  call assert_equal(string(trunc(-2.9)), '-2.0')
-  call assert_equal(string(trunc(0.0/0.0)), 'nan')
-  call assert_equal(string(trunc(1.0/0.0)), 'inf')
-  call assert_equal(string(trunc(-1.0/0.0)), '-inf')
+  call assert_equal('2.0', string(trunc(2.1)))
+  call assert_equal('2.0', string(trunc(2.5)))
+  call assert_equal('2.0', string(trunc(2.9)))
+  call assert_equal('-2.0', string(trunc(-2.1)))
+  call assert_equal('-2.0', string(trunc(-2.5)))
+  call assert_equal('-2.0', string(trunc(-2.9)))
+  call assert_equal('nan', string(trunc(0.0/0.0)))
+  call assert_equal('inf', string(trunc(1.0/0.0)))
+  call assert_equal('-inf', string(trunc(-1.0/0.0)))
 endfunc
 
 func Test_isnan()
-  call assert_equal(isnan(1.0), 0)
-  call assert_equal(isnan(0.0/0.0), 1)
-  call assert_equal(isnan(1.0/0.0), 0)
-  call assert_equal(isnan('a'), 0)
-  call assert_equal(isnan([]), 0)
+  call assert_equal(0, isnan(1.0))
+  call assert_equal(1, isnan(0.0/0.0))
+  call assert_equal(0, isnan(1.0/0.0))
+  call assert_equal(0, isnan('a'))
+  call assert_equal(0, isnan([]))
 endfunc
diff --git a/src/version.c b/src/version.c
index 824a292..38be7db 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    158,
+/**/
     157,
 /**/
     156,