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diff --git a/newlib/libm/machine/riscv/fetestexcept.c b/newlib/libm/machine/riscv/fetestexcept.c
new file mode 100644
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+++ b/newlib/libm/machine/riscv/fetestexcept.c
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+/*
+  (c) Copyright 2017 Michael R. Neilly
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions
+  are met:
+
+  * Redistributions of source code must retain the above copyright
+  notice, this list of conditions and the following disclaimer.
+
+  * Redistributions in binary form must reproduce the above copyright
+  notice, this list of conditions and the following disclaimer in the
+  documentation and/or other materials provided with the distribution.
+
+  * Neither the names of the copyright holders nor the names of their
+  contributors may be used to endorse or promote products derived from
+  this software without specific prior written permission.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+  COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+  POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#include <fenv.h>
+
+/* This implementation is intended to comply with the following
+ * specification:
+ *
+ * http://pubs.opengroup.org/onlinepubs/9699919799/functions/fetestexcept.html
+ *
+ * "The fetestexcept() function shall determine which of a specified
+ * subset of the floating-point exception flags are currently set. The
+ * excepts argument specifies the floating-point status flags to be
+ * queried."
+ */
+
+int fetestexcept(int excepts)
+{
+
+#if __riscv_flen
+
+  /* Mask excepts to be sure only supported flag bits are set */
+
+  excepts &= FE_ALL_EXCEPT;
+
+  /* Read the current flags */
+
+  fexcept_t flags;
+  asm volatile("frflags %0" : "=r"(flags));
+
+  /* "The fetestexcept() function shall return the value of the
+   * bitwise-inclusive OR of the floating-point exception macros
+   * corresponding to the currently set floating-point exceptions
+   * included in excepts."
+   */
+
+  return (flags & excepts);
+
+#else
+
+  /* For soft float */
+
+  return 0;
+
+#endif
+
+}