updates.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@44761 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 29 insertions, 18 deletions

diff --git a/www/comparison.html b/www/comparison.html
index df79d6ec4b..7e6c1dfd6a 100644
--- a/www/comparison.html
+++ b/www/comparison.html
@@ -41,23 +41,25 @@
         the variants we are interested in.  clang's support for C++ in

         particular is nowhere near what GCC supports.</li>

     <li>GCC is popular and widely adopted.</li>

+    <li>GCC does not require a C++ compiler to build it.</li>

     </ul>

     

     <p>Pros of clang vs GCC:</p>

     

     <ul>

-    <li>GCC has a very old codebase which presents a steep learning curve to new

-        developers.  The Clang ASTs and design are intended to be easily

-        understandable to anyone who is familiar with the languages involved

-        and have a basic understanding of how a compiler works.</li>

-    <li>GCC is built as a monolithic static compiler, which makes it extremely

-        difficult to use as an API and integrate into other tools (e.g. an IDE).

-        Its historic design and <a 

+    <li>The Clang ASTs and design are intended to be easily understandable to

+        anyone who is familiar with the languages involved and who have a basic

+        understanding of how a compiler works.  GCC has a very old codebase

+        which presents a steep learning curve to new developers.</li>

+    <li>Clang is designed as an API from its inception, allowing it to be reused

+        by source analysis tools, refactoring, IDEs (etc) as well as for code

+        generation.  GCC is built as a monolithic static compiler, which makes

+        it extremely difficult to use as an API and integrate into other tools.

+        Further, its historic design and <a 

         href="http://gcc.gnu.org/ml/gcc/2007-11/msg00460.html">current</a>

         <a href="http://gcc.gnu.org/ml/gcc/2004-12/msg00888.html">policy</a> 

-        makes it difficult to decouple the front-end from

-        the rest of the compiler. Clang is designed as an API from its

-        inception.</li>

+        makes it difficult to decouple the front-end from the rest of the

+        compiler. </li>

     <li>Various GCC design decisions make it very difficult to reuse: its build

         system is difficult to modify, you can't link multiple targets into one

         binary, you can't link multiple front-ends into one binary, it uses a

@@ -70,18 +72,26 @@
     <li>GCC simplifies code as it parses it.  As one simple example, if you

         write "x-x" in your source code, the GCC AST will contain "0", with no

         mention of x.  This is extremely bad for a refactoring tool that wants

-        to rename 'x' for example.</li>

+        to rename 'x'.</li>

     <li>GCC does not have a way to serialize the AST of a file out to disk and 

         read it back into another program.  Its PCH mechanism is architecturally

-        only able to read the dump back into the exact same binary.</li>

-    <li>GCC is <a href="features.html#performance">very slow and uses a large 

-        amount of memory</a>.</li>

-    <li>The diagnostics produced by GCC are acceptable, but are often confusing

-        and it does not support <a 

-        href="features.html#expressivediags">expressive diagnostics</a>.</li>

+        only able to read the dump back into the exact same executable as the

+        one that produced it.</li>

+    <li>Clang is <a href="features.html#performance">much faster and uses far

+        less memory</a> than GCC.</li>

+    <li>Clang aims to provide extremely clear and concise diagnostics (error and

+        warning messages), and includes support for <a

+        href="features.html#expressivediags">expressive diagnostics</a>.  GCC's

+        warnings are acceptable, but are often confusing and it does not support

+        expressive diagnostics.  Clang also preserves typedefs in diagnostics

+        consistently.</li>

     <li>GCC is licensed under the GPL license.  clang uses a BSD license, which

         allows it to be used by projects that do not themselves want to be

         GPL.</li>

+    <li>Clang inherits a number of features from its use of LLVM as a backend,

+        including support for a bytecode representation for intermediate code,

+        pluggable optimizers, link-time optimization support, Just-In-Time

+        compilation, etc.</li>

     </ul>

 

     <!--=====================================================================-->

@@ -143,7 +153,8 @@
     <ul>

     <li>PCC dates from the 1970's and has been dormant for most of that time.

         The clang + llvm community are very active.</li>

-    <li>PCC doesn't support Objective-C and doesn't aim to support C++.</li>

+    <li>PCC doesn't support C99, Objective-C, and doesn't aim to support

+        C++.</li>

     <li>PCC's code generation is very limited compared to LLVM, it produces very

         inefficient code and does not support many important targets.</li>

     <li>PCC's does not have an integrated preprocessor, so it is extremely