From cdd63adfcdcc40cb48fc52bb36c9876a888625cb Mon Sep 17 00:00:00 2001
From: John Maddock <john@johnmaddock.co.uk>
Date: Sat, 8 Jun 2013 14:07:21 +0000
Subject: [PATCH] Fix assignment operations to be safe after a move. Added test
 cases to catch bug case. Refs #8667.

[SVN r84687]
---
 include/boost/multiprecision/gmp.hpp  | 10 +++---
 include/boost/multiprecision/mpfr.hpp | 49 ++++++++++++++++++++++++---
 test/test_move.cpp                    | 45 ++++++++++++++++++++++++
 3 files changed, 95 insertions(+), 9 deletions(-)

diff --git a/include/boost/multiprecision/gmp.hpp b/include/boost/multiprecision/gmp.hpp
index 9e6f1579..e20bb915 100644
--- a/include/boost/multiprecision/gmp.hpp
+++ b/include/boost/multiprecision/gmp.hpp
@@ -1015,8 +1015,9 @@ struct gmp_int
    explicit gmp_int(const gmp_rational& o);
    gmp_int& operator = (const gmp_int& o)
    {
-      if(o.m_data[0]._mp_d)
-         mpz_set(m_data, o.m_data);
+      if(m_data[0]._mp_d == 0)
+         mpz_init(this->m_data);
+      mpz_set(m_data, o.m_data);
       return *this;
    }
 #ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
@@ -1728,8 +1729,9 @@ struct gmp_rational
    }
    gmp_rational& operator = (const gmp_rational& o)
    {
-      if(o.m_data[0]._mp_num._mp_d)
-         mpq_set(m_data, o.m_data);
+      if(m_data[0]._mp_den._mp_d == 0)
+         mpq_init(m_data);
+      mpq_set(m_data, o.m_data);
       return *this;
    }
 #ifndef BOOST_NO_CXX11_RVALUE_REFERENCES
diff --git a/include/boost/multiprecision/mpfr.hpp b/include/boost/multiprecision/mpfr.hpp
index b7aa784c..81d8c112 100644
--- a/include/boost/multiprecision/mpfr.hpp
+++ b/include/boost/multiprecision/mpfr.hpp
@@ -702,21 +702,29 @@ struct mpfr_float_backend : public detail::mpfr_float_imp<digits10, AllocationTy
    }
    mpfr_float_backend& operator=(const mpfr_t val)
    {
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, multiprecision::detail::digits10_2_2(digits10));
       mpfr_set(this->m_data, val, GMP_RNDN);
       return *this;
    }
    mpfr_float_backend& operator=(const mpf_t val)
    {
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, multiprecision::detail::digits10_2_2(digits10));
       mpfr_set_f(this->m_data, val, GMP_RNDN);
       return *this;
    }
    mpfr_float_backend& operator=(const mpz_t val)
    {
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, multiprecision::detail::digits10_2_2(digits10));
       mpfr_set_z(this->m_data, val, GMP_RNDN);
       return *this;
    }
    mpfr_float_backend& operator=(const mpq_t val)
    {
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, multiprecision::detail::digits10_2_2(digits10));
       mpfr_set_q(this->m_data, val, GMP_RNDN);
       return *this;
    }
@@ -724,22 +732,30 @@ struct mpfr_float_backend : public detail::mpfr_float_imp<digits10, AllocationTy
    template <unsigned D, mpfr_allocation_type AT>
    mpfr_float_backend& operator=(const mpfr_float_backend<D, AT>& val)
    {
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, multiprecision::detail::digits10_2_2(digits10));
       mpfr_set(this->m_data, val.data(), GMP_RNDN);
       return *this;
    }
    template <unsigned D>
    mpfr_float_backend& operator=(const gmp_float<D>& val)
    {
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, multiprecision::detail::digits10_2_2(digits10));
       mpfr_set_f(this->m_data, val.data(), GMP_RNDN);
       return *this;
    }
    mpfr_float_backend& operator=(const gmp_int& val)
    {
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, multiprecision::detail::digits10_2_2(digits10));
       mpfr_set_z(this->m_data, val.data(), GMP_RNDN);
       return *this;
    }
    mpfr_float_backend& operator=(const gmp_rational& val)
    {
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, multiprecision::detail::digits10_2_2(digits10));
       mpfr_set_q(this->m_data, val.data(), GMP_RNDN);
       return *this;
    }
@@ -803,7 +819,10 @@ struct mpfr_float_backend<0, allocate_dynamic> : public detail::mpfr_float_imp<0
 
    mpfr_float_backend& operator=(const mpfr_float_backend& o)
    {
-      mpfr_set_prec(this->m_data, mpfr_get_prec(o.data()));
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, mpfr_get_prec(o.data()));
+      else
+         mpfr_set_prec(this->m_data, mpfr_get_prec(o.data()));
       mpfr_set(this->m_data, o.data(), GMP_RNDN);
       return *this;
    }
@@ -822,47 +841,67 @@ struct mpfr_float_backend<0, allocate_dynamic> : public detail::mpfr_float_imp<0
    }
    mpfr_float_backend& operator=(const mpfr_t val)
    {
-      mpfr_set_prec(this->m_data, mpfr_get_prec(val));
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, mpfr_get_prec(val));
+      else
+         mpfr_set_prec(this->m_data, mpfr_get_prec(val));
       mpfr_set(this->m_data, val, GMP_RNDN);
       return *this;
    }
    mpfr_float_backend& operator=(const mpf_t val)
    {
-      mpfr_set_prec(this->m_data, mpf_get_prec(val));
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, mpf_get_prec(val));
+      else
+         mpfr_set_prec(this->m_data, mpf_get_prec(val));
       mpfr_set_f(this->m_data, val, GMP_RNDN);
       return *this;
    }
    mpfr_float_backend& operator=(const mpz_t val)
    {
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, multiprecision::detail::digits10_2_2(get_default_precision()));
       mpfr_set_z(this->m_data, val, GMP_RNDN);
       return *this;
    }
    mpfr_float_backend& operator=(const mpq_t val)
    {
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, multiprecision::detail::digits10_2_2(get_default_precision()));
       mpfr_set_q(this->m_data, val, GMP_RNDN);
       return *this;
    }
    template <unsigned D>
    mpfr_float_backend& operator=(const mpfr_float_backend<D>& val)
    {
-      mpfr_set_prec(this->m_data, mpfr_get_prec(val.data()));
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, mpfr_get_prec(val.data()));
+      else
+         mpfr_set_prec(this->m_data, mpfr_get_prec(val.data()));
       mpfr_set(this->m_data, val.data(), GMP_RNDN);
       return *this;
    }
    template <unsigned D>
    mpfr_float_backend& operator=(const gmp_float<D>& val)
    {
-      mpfr_set_prec(this->m_data, mpf_get_prec(val.data()));
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, mpf_get_prec(val.data()));
+      else
+         mpfr_set_prec(this->m_data, mpf_get_prec(val.data()));
       mpfr_set_f(this->m_data, val.data(), GMP_RNDN);
       return *this;
    }
    mpfr_float_backend& operator=(const gmp_int& val)
    {
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, multiprecision::detail::digits10_2_2(get_default_precision()));
       mpfr_set_z(this->m_data, val.data(), GMP_RNDN);
       return *this;
    }
    mpfr_float_backend& operator=(const gmp_rational& val)
    {
+      if(this->m_data[0]._mpfr_d == 0)
+         mpfr_init2(this->m_data, multiprecision::detail::digits10_2_2(get_default_precision()));
       mpfr_set_q(this->m_data, val.data(), GMP_RNDN);
       return *this;
    }
diff --git a/test/test_move.cpp b/test/test_move.cpp
index a2e8b04c..c5c5ab3b 100644
--- a/test/test_move.cpp
+++ b/test/test_move.cpp
@@ -84,6 +84,36 @@ void test_std_lib()
    BOOST_TEST(b == 2);
 }
 
+template <class T, class A>
+void test_move_and_assign(T x, A val)
+{
+   // move away from x, then assign val to x.
+   T z(x);
+   T y(std::move(x));
+   x.assign(val);
+   BOOST_CHECK_EQUAL(x, T(val));
+   BOOST_CHECK_EQUAL(z, y);
+}
+
+template <class T>
+void test_move_and_assign()
+{
+   T x(23);
+   test_move_and_assign(x, static_cast<short>(2));
+   test_move_and_assign(x, static_cast<int>(2));
+   test_move_and_assign(x, static_cast<long>(2));
+   test_move_and_assign(x, static_cast<long long>(2));
+   test_move_and_assign(x, static_cast<unsigned short>(2));
+   test_move_and_assign(x, static_cast<unsigned int>(2));
+   test_move_and_assign(x, static_cast<unsigned long>(2));
+   test_move_and_assign(x, static_cast<unsigned long long>(2));
+   test_move_and_assign(x, static_cast<float>(2));
+   test_move_and_assign(x, static_cast<double>(2));
+   test_move_and_assign(x, static_cast<long double>(2));
+   test_move_and_assign(x, x);
+   test_move_and_assign(x, "23");
+}
+
 
 int main()
 {
@@ -131,6 +161,9 @@ int main()
       d = std::move(e);
       e = d;
       BOOST_TEST(e == d);
+
+      test_move_and_assign<mpfr_float>();
+      test_move_and_assign<mpfr_float_50>();
    }
 #endif
 #ifdef TEST_GMP
@@ -170,6 +203,9 @@ int main()
       d = std::move(e);
       e = d;
       BOOST_TEST(e == d);
+
+      test_move_and_assign<mpf_float>();
+      test_move_and_assign<mpf_float_50>();
    }
    {
       test_std_lib<mpz_int>();
@@ -194,6 +230,8 @@ int main()
       d = std::move(e);
       e = d;
       BOOST_TEST(e == d);
+
+      test_move_and_assign<mpz_int>();
    }
    {
       test_std_lib<mpq_rational>();
@@ -217,6 +255,8 @@ int main()
       d = std::move(e);
       e = d;
       BOOST_TEST(e == d);
+
+      test_move_and_assign<mpq_rational>();
    }
 #endif
 #ifdef TEST_TOMMATH
@@ -245,6 +285,8 @@ int main()
       d = std::move(e);
       e = d;
       BOOST_TEST(e == d);
+
+      test_move_and_assign<tom_int>();
    }
 #endif
 #ifdef TEST_CPP_INT
@@ -273,6 +315,9 @@ int main()
       d = std::move(e);
       e = d;
       BOOST_TEST(e == d);
+
+      test_move_and_assign<cpp_int>();
+      test_move_and_assign<int512_t>();
    }
 #endif
    return boost::report_errors();