[libc-commits] [PATCH] D145821: [libc][NFC] add an atof test for a fuzz failure

[Michael Jones via Phabricator via libc-commits]

michaelrj created this revision.
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The differential fuzzer found that glibc and our libc disagree on the
result for "0x30000002222225p-1077", with ours being rounded up and
theirs rounded down. Ours is more correct for the nearest rounding mode,
so only a test is added.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D145821

Files:
  libc/test/src/stdlib/strtod_test.cpp


Index: libc/test/src/stdlib/strtod_test.cpp
===================================================================
--- libc/test/src/stdlib/strtod_test.cpp
+++ libc/test/src/stdlib/strtod_test.cpp
@@ -191,4 +191,8 @@
            "NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN?",
            0, uint64_t(0));
   run_test("0x.666E40", 9, uint64_t(0x3fd99b9000000000));
+
+  // glibc disagrees with this result, but ours is correct for the nearest
+  // rounding mode.
+  run_test("0x30000002222225p-1077", 22, uint64_t(0x0006000000444445), ERANGE);
 }


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