2007-09-03 Atsushi Enomoto <atsushi@ximian.com>

[mono.git] / web / faq

diff --git a/web/faq b/web/faq
index c1c6aa6d542811495cb4ea77fc8ed8dce6342ed1..9a45337118c2e089c7e98e171087c1c6bb50946f 100644 (file)
--- a/web/faq
+++ b/web/faq
@@ -207,7 +207,7 @@ A: Of course not.  Novell is a supporter of the Mono project, but the only way
    community to get involved. Visit the <a href="contributing.html">contributing</a> 
    page if you'd like to help out.
 
    community to get involved. Visit the <a href="contributing.html">contributing</a> 
    page if you'd like to help out.
 

-Q: What pieces Novell be working on?
+Q: What pieces is Novell working on?

 
 A: We will devote most of our resources to work on the pieces which are
    on the critical path to release a development and execution
 
 A: We will devote most of our resources to work on the pieces which are
    on the critical path to release a development and execution


@@ -533,12 +533,12 @@ fi
 
 Q: What architectures does Mono support?
 
 
 Q: What architectures does Mono support?
 

-A: Mono today ships with a Just-in-Time compiler for x86-based
-   systems.  It is tested regularly on Linux, FreeBSD and Windows
-   (with the XP/NT core).
+A: Mono today ships with a Just-in-Time compiler for x86, PowerPC and
+   SPARC-based systems.  It is tested regularly on Linux, FreeBSD and
+   Windows (with the XP/NT core).

 
    There is also an interpreter, which is slower that runs on the
 
    There is also an interpreter, which is slower that runs on the

-   s390, SPARC and PowerPC architectures.
+   s390, SPARC, HPPA, StrongARM and PowerPC architectures.

 
 Q: Can Mono run on Windows 9x, or ME editions?
 
 
 Q: Can Mono run on Windows 9x, or ME editions?
 


@@ -723,11 +723,11 @@ A: Most of Mono is being written using C#, with only
 
      <li> A multi-platform runtime engine: both a JIT engine and an
           interpreter exist.  The JIT engine runs currently on x86,
 
      <li> A multi-platform runtime engine: both a JIT engine and an
           interpreter exist.  The JIT engine runs currently on x86,

-          PowerPC and Sparc systems, while the interpreter works on
+          PowerPC Sparc and S390 systems, while the interpreter works on

           x86, SPARC, StrongARM, s390 and PowerPC systems.  
 
           x86, SPARC, StrongARM, s390 and PowerPC systems.  
 

-         The JIT engine is being ported to PowerPC, s390, SPARC and
-          amd64 systems as of this time.
+         The JIT engine is being ported to amd64 systems as of this
+         time. 

 
      <li> Supports Linux, BSD, MacOS, Windows and Solaris at this point.
 
 
      <li> Supports Linux, BSD, MacOS, Windows and Solaris at this point.
 


@@ -767,7 +767,9 @@ A: Most of Mono is being written using C#, with only
           Portable.NET's compiler.
 
      <li> Mono's C# compiler has strong error handling and has closer
           Portable.NET's compiler.
 
      <li> Mono's C# compiler has strong error handling and has closer

-          adherence to the specification.
+          adherence to the specification with support for definite
+         assignment (required to generate verifiable IL code) and 
+         CLS conformance checking.

 
      <li> Mono's C# compiler is written in C# which is easier for new
           developers to come in and improve, fix and tune.  The Mono
 
      <li> Mono's C# compiler is written in C# which is easier for new
           developers to come in and improve, fix and tune.  The Mono


@@ -782,15 +784,14 @@ A: Most of Mono is being written using C#, with only
           are important for advanced applications, compilers and
           dynamic code generation.
 
           are important for advanced applications, compilers and
           dynamic code generation.
 

-     <li> Mono has a <a href="xml-classes">complete managed XML
+     <li> Mono has a <a href="xml-classes.html">complete managed XML

           stack</a>: XML, XPath, XML Serializer, XML Schema handling
           are fully functional, feature complete and tuned for
           performance.
 
           stack</a>: XML, XPath, XML Serializer, XML Schema handling
           are fully functional, feature complete and tuned for
           performance.
 

-     <li> Mono has a complete cryptography stack: we have a complete
-          crypto stack: we implement the 1.0 and 1.1 APIs as well as
-          using our fully managed stack to implement the SSL/TLS
-          transports. 
+     <li> Mono has a <a href="crypto.html">complete cryptography stack
+         </a>: we implement the 1.0 and 1.1 APIs as well as using our
+         fully managed stack to implement the SSL/TLS transports. 

 
      <li> <a href="ado-net.html">Extensive database support</a>: Mono
           ships with database provides for <a
 
      <li> <a href="ado-net.html">Extensive database support</a>: Mono
           ships with database provides for <a


@@ -800,7 +801,7 @@ A: Most of Mono is being written using C#, with only
           href="tdsclient.html">SQL Server</a>, <a
           href="sqlite.html">SQL Lite</a>, <a
           href="mysql.html">MySQL</a>, <a
           href="tdsclient.html">SQL Server</a>, <a
           href="sqlite.html">SQL Lite</a>, <a
           href="mysql.html">MySQL</a>, <a

-          href="postgresql">PostgresSQL</A>, <a href="oledb.html">Ole
+          href="postgresql.html">PostgresSQL</A>, <a href="oledb.html">Ole

           DB</a> and <a href="odbc.html">ODBC</a>.
 
      <li> Mono includes full LDAP support.
           DB</a> and <a href="odbc.html">ODBC</a>.
 
      <li> Mono includes full LDAP support.


@@ -925,12 +926,11 @@ A: To upgrade your class libraries and compiler, see the
    3.- Then checkout or update your mcs CVS copy. Then follow 
    the steps described in mcs/INSTALL.txt.
 
    3.- Then checkout or update your mcs CVS copy. Then follow 
    the steps described in mcs/INSTALL.txt.
 

-Q: Will it be possible to use the CLI features without using byte codes
-   or the JIT?
+Q: Will it be possible to use the CLI features without using byte codes or the JIT?

 
 A: Yes. The CLI engine will be made available as a shared library.
    The garbage collection engine, the threading abstraction, the
 
 A: Yes. The CLI engine will be made available as a shared library.
    The garbage collection engine, the threading abstraction, the

-   object system, the dynamic type code system and the JIT will be
+   object system, the dynamic type code system and the JIT are

    available for C developers to integrate with their applications if
    they wish to do so. 
 
    available for C developers to integrate with their applications if
    they wish to do so. 
 


@@ -1347,11 +1347,30 @@ A: This has been done.
 <a name="gcc"></a>
 ** Mono and GCC
 
 <a name="gcc"></a>
 ** Mono and GCC
 

-Q: Are you working on a GCC front-end to C#? A GCC back-end that will
-   generate CIL images? 
+Q: Are you working on a GCC front-end to C#? 

 
 

-A: We would love to see a GCC modification that would generate CIL
-   images, but there is nothing at this point.
+A: We are not working on a GCC front-end for C#
+
+Q: Will you support C/C++ on the Mono VM?
+
+A:The open64 compiler effort from SGI helps a lot in this direction.
+
+   The Open64 compiler is a modified version of GCC that
+   generates a new intermediate language instead of RTL.  This could be
+   the foundation to generate CIL code, and to implement the upcoming
+   Managed extensions to C++ from ECMA.
+
+   Open64 (and other derivative forks of GCC) split the gcc front-ends
+   from the backends by using the WHIRL intermediate representation.  
+   Kris has begun the implementation of a translator from WHIRL to CIL.
+
+   So it will be possible to use the GCC compilers to target the CIL.
+
+Q: What about Managed C++?
+
+A: Once a full translator for WHIRL exists, we are interested in
+   looking at expanding the GCC frontends to include extensions for
+   Managed C++.

 
 Q: What about making a front-end to GCC that takes CIL images and
    generates native code?
 
 Q: What about making a front-end to GCC that takes CIL images and
    generates native code?


@@ -1359,11 +1378,6 @@ Q: What about making a front-end to GCC that takes CIL images and
 A: There is no active work on this area, but Mono already provides
    pre-compilation services (Ahead-of-Time compilation).
 
 A: There is no active work on this area, but Mono already provides
    pre-compilation services (Ahead-of-Time compilation).
 

-Q: But would this work around the GPL in the GCC compiler and allow
-   people to work on non-free front-ends?
-
-A: People can already do this by targeting the JVM byte codes (there
-   are about 130 compilers for various languages that target the JVM).

 
 <a name="performance"></a>
 ** Performance
 
 <a name="performance"></a>
 ** Performance


@@ -1377,10 +1391,19 @@ A: We can not predict the future, but a conservative estimate is that
    many new features, and layers suitable for optimization.  It is
    relatively easy to add new optimizations to Mono. 
 
    many new features, and layers suitable for optimization.  It is
    relatively easy to add new optimizations to Mono. 
 

-   The CIL has some advantages over the Java byte code:  it is really
-   an intermediate representation and there are a number of
-   restrictions on how you can emit CIL code that simplify creating
-   better JIT engines.
+   The CIL has some advantages over the Java byte code: The existance
+   of structs in addition to classes helps a lot the performance and
+   minimizes the memory footprint of applications.
+
+   Generics in the CLI world are first-class citizens, they are not
+   just a strong-typing addition to the language.  The generic
+   specifications are embedded into the instruction stream, the JIT
+   uses this information to JIT a unique instances of a method that is
+   optimized for the type arguments.
+
+   The CIL is really an intermediate representation and there are a
+   number of restrictions on how you can emit CIL code that simplify
+   creating better JIT engines.

 
    For example, on the CIL, the stack is not really an abstraction
    available for the code generator to use at will.  Rather, it is a
 
    For example, on the CIL, the stack is not really an abstraction
    available for the code generator to use at will.  Rather, it is a


@@ -1456,7 +1479,7 @@ A: First some background information.
    Microsoft falls under the ECMA/ISO submission.  Jim Miller at
    Microsoft has made a statement on the patents covering ISO/ECMA,
    (he is one of the inventors listed in the patent): <a
    Microsoft falls under the ECMA/ISO submission.  Jim Miller at
    Microsoft has made a statement on the patents covering ISO/ECMA,
    (he is one of the inventors listed in the patent): <a

-   href="https://mailserver.di.unipi.it/pipermail/dotnet-sscli/msg00218.html">here</a>.
+   href="http://web.archive.org/web/20030609164123/http://mailserver.di.unipi.it/pipermail/dotnet-sscli/msg00218.html">here</a>.

 
    Basically a grant is given to anyone who want to implement those
    components for free and for any purpose.
 
    Basically a grant is given to anyone who want to implement those
    components for free and for any purpose.


@@ -1628,8 +1651,12 @@ A: It's possible to run VC++ generated apps under Mono, but we do not
 
 Q: Does Mono support generics?.
 
 
 Q: Does Mono support generics?.
 

-A: Mono doesn't support generics currently but a lot of work is being 
-   done towards it.
+A: Yes, the Mono runtime now supports the new Generics extensions, and
+   there is also support for generics in our new compiler: `gmcs'.
+
+   The Mono C# 1.0 compiler (mcs) will ship with various C# 2.0
+   features, but generics will remain on the separate compiler (gmcs)
+   as this code is not as tested as the main compiler.

 
 <a name="problems"></a>
 ** Mono Common Problems
 
 <a name="problems"></a>
 ** Mono Common Problems