From 99b44c02422e2baa423071724714b58c46ae60a3 Mon Sep 17 00:00:00 2001
From: Pavel Kirienko <pavel.kirienko@gmail.com>
Date: Fri, 17 Mar 2017 14:44:57 +0300
Subject: [PATCH] NuttX math lib workaround

---
 matrix/stdlib_imports.hpp | 39 ++++++++++++++++++++++++++++++++++++++-
 1 file changed, 38 insertions(+), 1 deletion(-)

diff --git a/matrix/stdlib_imports.hpp b/matrix/stdlib_imports.hpp
index 4d24b814cf..efeba31322 100644
--- a/matrix/stdlib_imports.hpp
+++ b/matrix/stdlib_imports.hpp
@@ -15,6 +15,42 @@
 
 namespace matrix {
 
+#if defined(__PX4_NUTTX)
+/*
+ * NuttX has no usable C++ math library, so we need to provide the needed definitions here manually.
+ */
+#define MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(name)                                   \
+	inline float       name(float x)       { return ::name##f(x); }          \
+	inline double      name(double x)      { return ::name(x); }             \
+        inline long double name(long double x) { return ::name##l(x); }
+
+#define MATRIX_NUTTX_WRAP_MATH_FUN_BINARY(name)                                                    \
+	inline float       name(float x, float y)             { return ::name##f(x, y); }          \
+	inline double      name(double x, double y)           { return ::name(x, y); }             \
+        inline long double name(long double x, long double y) { return ::name##l(x, y); }
+
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(fabs)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(log)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(log10)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(exp)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(sqrt)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(sin)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(cos)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(tan)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(asin)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(acos)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(atan)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(sinh)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(cosh)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(tanh)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(ceil)
+MATRIX_NUTTX_WRAP_MATH_FUN_UNARY(floor)
+
+MATRIX_NUTTX_WRAP_MATH_FUN_BINARY(pow)
+MATRIX_NUTTX_WRAP_MATH_FUN_BINARY(atan2)
+
+#else       // Not NuttX, using the C++ standard library
+
 using std::abs;
 using std::div;
 using std::fabs;
@@ -40,7 +76,7 @@ using std::frexp;
 using std::ldexp;
 using std::modf;
 
-#if (__cplusplus >= 201103L) && !defined(__PX4_NUTTX)
+# if (__cplusplus >= 201103L)
 
 using std::imaxabs;
 using std::imaxdiv;
@@ -88,6 +124,7 @@ using std::islessequal;
 using std::islessgreater;
 using std::isunordered;
 
+# endif
 #endif
 
 }