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@@ -24,7 +24,7 @@
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Similar to the
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<a href="borland_cpp.html">portability hints for Borland C++</a>,
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this page provides hints on some language features of the Microsoft Visual C++
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-version 6.0 servicepack 4 compiler.
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+version 6.0 service pack 4 compiler.
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Each entry in the following list describes a particular issue,
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complete with sample source code to demonstrate the effect.
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@@ -86,18 +86,18 @@ Trying to explicitly instantiate a function template leads to the
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wrong function being called silently.
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<pre>
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-#include <stdio.h>
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+#include <stdio.h>
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-template<class T>
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+template<class T>
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void f()
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{
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- printf("%d\n", sizeof(T));
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+ printf("%d\n", sizeof(T));
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}
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int main()
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{
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- f<double>(); // output: "1"
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- f<char>(); // output: "1"
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+ f<double>(); // output: "1"
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+ f<char>(); // output: "1"
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return 0;
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}
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</pre>
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@@ -134,7 +134,7 @@ not work.
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<pre>
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struct A
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{
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- static const int i = 5; // "invalid syntax for pure virtual method"
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+ static const int i = 5; // "invalid syntax for pure virtual method"
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};
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</pre>
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@@ -164,13 +164,13 @@ void g()
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A Template cannot be declared a friend of a class.
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<pre>
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-template<class T>
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+template<class T>
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struct A {};
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struct B
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{
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- template<class T>
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- friend struct A; // "syntax error"
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+ template<class T>
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+ friend struct A; // "syntax error"
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};
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</pre>
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@@ -181,16 +181,16 @@ templates</h3>
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Defining member templates outside their enclosing class does not work.
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<pre>
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-template<class T>
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+template<class T>
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struct A
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{
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- template<class U>
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+ template<class U>
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void f();
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};
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-template<class T>
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-template<class U> // "syntax error"
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-void A<T>::f() // "T: undeclared identifier"
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+template<class T>
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+template<class U> // "syntax error"
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+void A<T>::f() // "T: undeclared identifier"
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{
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}
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</pre>
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@@ -204,14 +204,14 @@ their enclosing class.
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Partial specialization of class templates does not work.
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<pre>
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-template<class T>
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+template<class T>
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struct A {};
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-template<class T>
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+template<class T>
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struct B {};
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-template<class T>
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-struct A<B<T> > {}; // template class was already defined as a non-template
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+template<class T>
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+struct A<B<T> > {}; // template class was already defined as a non-template
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</pre>
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<strong>Workaround:</strong> In some situations where interface
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@@ -219,17 +219,17 @@ does not matter, member class templates can simulate partial
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specialization.
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-<h3>[template-value] Dependent emplate value parameters</h3>
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+<h3>[template-value] Dependent template value parameters</h3>
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Template value parameters whose type depends on a previous template
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parameter provoke an internal compiler error if the correct syntax
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(with "typename") is used.
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<pre>
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-template<class T, typename T::result_type> // C1001: INTERNAL COMPILER ERROR: ms
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+template<class T, typename T::result_type> // C1001: INTERNAL COMPILER ERROR: ms
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c1.cpp, line 1794
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struct B {};
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- // (omit "typename" and it compiles)
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+ // (omit "typename" and it compiles)
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</pre>
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@@ -239,11 +239,21 @@ struct B {};
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The type <code>wchar_t</code> is not a built-in type.
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<pre>
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-wchar_t x; // "missing storage class or type identifier"
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+wchar_t x; // "missing storage class or type identifier"
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</pre>
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-<p>
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+<h2>
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+Standard Library</h2>
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+<h3>[clib-namespace] C library names in global namespace instead of std</h3>
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+<p>Library names from the <c...> headers are in the global namespace
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+instead of namespace std.<p><b>Workaround:</b> The header <a href="../libs/config/index.htm">boost/config.hpp</a>
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+will define BOOST_NO_STDC_NAMESPACE. It can be used as follows:
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+<pre># ifdef BOOST_NO_STDC_NAMESPACE
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+ namespace std { using ::abs; using ::fabs; }
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+# endif</pre>
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+<p>Because std::size_t and std::ptrdiff_t are so commonly used, the workaround
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+for these is already provided in boost/config.hpp.<p>
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<hr>
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2001-02-01 <a href="../people/jens_maurer.htm">Jens Maurer</a>
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