From b5cb4935c268f12e63b61e035b455b0a59e67aa2 Mon Sep 17 00:00:00 2001
From: Stephan Bergmann <sbergman@redhat.com>
Date: Thu, 22 May 2014 18:31:07 +0200
Subject: Work around undef conversion of large double to float

...as flagged by -fsanitize=undefined.  But is it really undefined?
[conv.double] "If the source value is between two adjacent destination values,
the result of the conversion is an implementation-defined choice of either of
those values."  So if the double is between std::numeric_limits<float>::max()
and std::numeric_limits<float>::infinity()...

Change-Id: I6389c8ac4a922991e240638d231dd2a39e173882
---
 sal/rtl/ustring.cxx | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

(limited to 'sal/rtl')

diff --git a/sal/rtl/ustring.cxx b/sal/rtl/ustring.cxx
index f10e755bbc7b..a79c9177a3ee 100644
--- a/sal/rtl/ustring.cxx
+++ b/sal/rtl/ustring.cxx
@@ -148,11 +148,26 @@ sal_Int32 SAL_CALL rtl_ustr_valueOfDouble(sal_Unicode * pStr, double d)
     return nLen;
 }
 
+namespace {
+
+// Avoid -fsanitize=undefined warning e.g. "runtime error: value 1e+99 is
+// outside the range of representable values of type 'float'":
+float doubleToFloat(double x) {
+    return
+        x < -std::numeric_limits<float>::max()
+        ? -std::numeric_limits<float>::infinity()
+        : x > std::numeric_limits<float>::max()
+        ? std::numeric_limits<float>::infinity()
+        : static_cast<float>(x);
+}
+
+}
+
 float SAL_CALL rtl_ustr_toFloat(sal_Unicode const * pStr) SAL_THROW_EXTERN_C()
 {
-    return (float) rtl_math_uStringToDouble(pStr,
+    return doubleToFloat(rtl_math_uStringToDouble(pStr,
                                             pStr + rtl_ustr_getLength(pStr),
-                                            '.', 0, 0, 0);
+                                            '.', 0, 0, 0));
 }
 
 double SAL_CALL rtl_ustr_toDouble(sal_Unicode const * pStr) SAL_THROW_EXTERN_C()
-- 
cgit