diff options
| author |  Benjamin Barenblat <bbaren@google.com> | 2021-01-31 15:02:36 -0500 |
|---|---|---|
| committer | Benjamin Barenblat <bbaren@google.com> | 2021-01-31 15:04:49 -0500 |
| commit | 1f93c7bc4f508dbc9d3eb2848b8d2b4cd572eb38 (patch) | |
| tree | f01199d13ac79fea90f734d42742b39e6e257efc | |
| parent | 9229f2a0b73adb577b85e30b3060862c1c583d1a (diff) | |
Work around GCC bug narrowing NaNs
Work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98251 by
preventing NaN narrowing in unit tests.
| -rw-r--r-- | debian/patches/nan-narrowing.diff | 25 | ||||
| -rw-r--r-- | debian/patches/series | 1 |
2 files changed, 26 insertions, 0 deletions
diff --git a/debian/patches/nan-narrowing.diff b/debian/patches/nan-narrowing.diff new file mode 100644 index 00000000..c7ec9325 --- /dev/null +++ b/debian/patches/nan-narrowing.diff @@ -0,0 +1,25 @@ +From: Benjamin Barenblat <bbaren@google.com> +Subject: Avoid libgcc -NaN narrowing bug +Forwarded: yes +Applied-Upstream: https://github.com/abseil/abseil-cpp/commit/1bae23e32ba1f1af7c7d1488a69a351ec96dc98d + +When testing -NaN parsing, avoid narrowing -NaN from double to float. This +avoids a bug in libgcc (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98251). + +The author works at Google. Upstream applied this patch as Piper revision +347654751 and exported it to GitHub; the Applied-Upstream URL above points to +the exported commit. + +--- a/absl/strings/charconv_test.cc ++++ b/absl/strings/charconv_test.cc +@@ -653,7 +653,9 @@ TEST(FromChars, NaNFloats) { + negative_from_chars_float); + EXPECT_TRUE(std::signbit(negative_from_chars_float)); + EXPECT_FALSE(Identical(negative_from_chars_float, from_chars_float)); +- from_chars_float = std::copysign(from_chars_float, -1.0); ++ // Use the (float, float) overload of std::copysign to prevent narrowing; ++ // see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98251. ++ from_chars_float = std::copysign(from_chars_float, -1.0f); + EXPECT_TRUE(Identical(negative_from_chars_float, from_chars_float)); + } + } diff --git a/debian/patches/series b/debian/patches/series index cf05a43f..9c73d904 100644 --- a/debian/patches/series +++ b/debian/patches/series @@ -3,3 +3,4 @@ fix-hppa.diff std-hash.diff latomic.diff cpu-frequency.diff +nan-narrowing.diff |