From: Yuriy Skalko <yuriy.skalko@gmail.com>
Date: Thu, 26 Nov 2020 21:01:18 +0000 (+0200)
Subject: Fix signed integer overflow on x = 0, detected by GCC sanitizer
X-Git-Tag: 2.4.0-alpha3~652
X-Git-Url: https://git.lyx.org/gitweb/?a=commitdiff_plain;h=fdefff1108d43739b6631015f55fb3cc94cfed2b;p=lyx.git

Fix signed integer overflow on x = 0, detected by GCC sanitizer
---

diff --git a/src/support/lstrings.cpp b/src/support/lstrings.cpp
index f0e79b88b3..9aac66a754 100644
--- a/src/support/lstrings.cpp
+++ b/src/support/lstrings.cpp
@@ -1446,8 +1446,8 @@ std::string formatFPNumber(double x)
 	os << std::fixed;
 	// Prevent outputs of 23.4200000000000017 but output small numbers
 	// with at least 6 significant digits.
-	double const logarithm = log10(fabs(x));
-	os << std::setprecision(max(6 - iround(logarithm), 0)) << x;
+	int const precision = (x == 0.0) ? 0 : max(6 - iround(log10(fabs(x))), 0);
+	os << std::setprecision(precision) << x;
 	string result = os.str();
 	if (result.find('.') != string::npos) {
 		result = rtrim(result, "0");