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diff --git a/gfx/harfbuzz/src/hb-number-parser.rl b/gfx/harfbuzz/src/hb-number-parser.rl
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+/*
+ * Copyright © 2019  Ebrahim Byagowi
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ */
+
+#ifndef HB_NUMBER_PARSER_HH
+#define HB_NUMBER_PARSER_HH
+
+#include "hb.hh"
+
+%%{
+
+machine double_parser;
+alphtype unsigned char;
+write data;
+
+action see_neg { neg = true; }
+action see_exp_neg { exp_neg = true; }
+
+action add_int  {
+	value = value * 10. + (fc - '0');
+}
+action add_frac {
+	if (likely (frac <= MAX_FRACT / 10))
+	{
+	  frac = frac * 10. + (fc - '0');
+	  ++frac_count;
+	}
+}
+action add_exp  {
+	if (likely (exp * 10 + (fc - '0') <= MAX_EXP))
+	  exp = exp * 10 + (fc - '0');
+	else
+	  exp_overflow = true;
+}
+
+num = [0-9]+;
+
+main := (
+	(
+		(('+'|'-'@see_neg)? num @add_int) ('.' num @add_frac)?
+		|
+		(('+'|'-'@see_neg)? '.' num @add_frac)
+	)
+	(('e'|'E') (('+'|'-'@see_exp_neg)? num @add_exp))?
+);
+
+}%%
+
+/* Works only for n < 512 */
+static inline double
+_pow10 (unsigned exponent)
+{
+  static const double _powers_of_10[] =
+  {
+    1.0e+256,
+    1.0e+128,
+    1.0e+64,
+    1.0e+32,
+    1.0e+16,
+    1.0e+8,
+    10000.,
+    100.,
+    10.
+  };
+  unsigned mask = 1 << (ARRAY_LENGTH (_powers_of_10) - 1);
+  double result = 1;
+  for (const double *power = _powers_of_10; mask; ++power, mask >>= 1)
+    if (exponent & mask) result *= *power;
+  return result;
+}
+
+/* a variant of strtod that also gets end of buffer in its second argument */
+static inline double
+strtod_rl (const char *p, const char **end_ptr /* IN/OUT */)
+{
+  double value = 0;
+  double frac = 0;
+  double frac_count = 0;
+  unsigned exp = 0;
+  bool neg = false, exp_neg = false, exp_overflow = false;
+  const unsigned long long MAX_FRACT = 0xFFFFFFFFFFFFFull; /* 2^52-1 */
+  const unsigned MAX_EXP = 0x7FFu; /* 2^11-1 */
+
+  const char *pe = *end_ptr;
+  while (p < pe && ISSPACE (*p))
+    p++;
+
+  int cs;
+  %%{
+    write init;
+    write exec;
+  }%%
+
+  *end_ptr = p;
+
+  if (frac_count) value += frac / _pow10 (frac_count);
+  if (neg) value *= -1.;
+
+  if (unlikely (exp_overflow))
+  {
+    if (value == 0) return value;
+    if (exp_neg)    return neg ? -DBL_MIN : DBL_MIN;
+    else            return neg ? -DBL_MAX : DBL_MAX;
+  }
+
+  if (exp)
+  {
+    if (exp_neg) value /= _pow10 (exp);
+    else         value *= _pow10 (exp);
+  }
+
+  return value;
+}
+
+#endif /* HB_NUMBER_PARSER_HH */