Implemented float.h

and improved math.h

libc/include/float.h

@@ -0,0 +1,33 @@
+#ifndef _FLOAT_H
+#define _FLOAT_H
+
+#define FLT_DIG        6          // Float precision: 6 decimal digits
+#define DBL_DIG        15         // Double precision: 15 decimal digits
+#define LDBL_DIG       18         // Long double precision: 18 decimal digits
+
+#define FLT_MAX        3.40282347e+38F   // Maximum float value
+#define DBL_MAX        1.7976931348623157e+308  // Maximum double value
+#define LDBL_MAX       1.189731495357231765e+4932L  // Max long double
+
+#define FLT_MIN        1.17549435e-38F   // Minimum positive normalized float
+#define DBL_MIN        2.2250738585072014e-308  // Min positive double
+#define LDBL_MIN       3.36210314311209350626e-4932L  // Min positive long double
+
+#define FLT_EPSILON    1.19209290e-7F    // Smallest float increment
+#define DBL_EPSILON    2.2204460492503131e-16  // Smallest double increment
+#define LDBL_EPSILON   1.08420217248550443401e-19L  // Smallest long double increment
+
+#define FLT_MAX_EXP    128       // Max exponent for float
+#define DBL_MAX_EXP    1024      // Max exponent for double
+#define LDBL_MAX_EXP   16384     // Max exponent for long double
+
+#define FLT_MIN_EXP    -125      // Min exponent for float
+#define DBL_MIN_EXP    -1021     // Min exponent for double
+#define LDBL_MIN_EXP   -16381    // Min exponent for long double
+
+#define FLT_RADIX      2         // Floating-point base (usually 2)
+#define FLT_MANT_DIG   24        // Number of digits in float mantissa
+#define DBL_MANT_DIG   53        // Number of digits in double mantissa
+#define LDBL_MANT_DIG  64        // Number of digits in long double mantissa
+
+#endif

libc/math/const.c

@@ -1,4 +1,5 @@
 #include <math.h>
+#include <string.h>
 
 double nan(const char* tagp) {
     (void)tagp;

libc/math/htrig.c

@@ -11,6 +11,6 @@ double cosh(double x) {
 double tanh(double x) {
     double ex = exp(x);
     double emx = exp(-x);
-    return (ex - exp) / (ex + exp);
+    return (ex - emx) / (ex + emx);
 }