Modified the linker so that it always links in an object from an archive

[oota-llvm.git] / docs / FAQ.html

diff --git a/docs/FAQ.html b/docs/FAQ.html
index 8f9a9a7b69715537f52330c766b309bc36f52f50..f4afc266cbcbb34aa113c7267561a199d60a23bf 100644 (file)
--- a/docs/FAQ.html
+++ b/docs/FAQ.html
@@ -48,7 +48,7 @@
   errors.</li>
   <li>I've built LLVM and am testing it, but the tests freeze.</li>
   <li>Why do test results differ when I perform different types of builds?</li>
-  <li>Compiling LLVM with GCC 3.3 on SuSE 9 fails, what should I do?</li>
+  <li>Compiling LLVM with GCC 3.3.2 fails, what should I do?</li>
   </ol></li>
 
   <li><a href="#cfe">Using the GCC Front End</a>
@@ -70,6 +70,7 @@
   <ol>
      <li>What is this <tt>__main()</tt> call that gets inserted into
          <tt>main()</tt>?</li>
+     <li>Where did all of my code go??</li>
   </ol>
   </li>
 </ol>
@@ -329,12 +330,12 @@ build.</p>
 </div>
 
 <div class="question">
-<p>Compiling LLVM with GCC 3.3 on SuSE 9 fails, what should I do?</p>
+<p>Compiling LLVM with GCC 3.3.2 fails, what should I do?</p>
 </div>
 
 <div class="answer">
-<p>This is a bug in the customized version of GCC shipped with SuSE, and effects
-   projects other than LLVM.  Complain loudly to SuSE.  :)</p>
+<p>This is <a href="http://gcc.gnu.org/PR?13392">a bug in GCC</a>, and 
+   affects projects other than LLVM.  Try upgrading or downgrading your GCC.</p>
 </div>
 
 <!-- *********************************************************************** -->
@@ -406,11 +407,9 @@ directory inside of the LLVM GCC distribution.
   <a name="cfe_code">Questions about code generated by the GCC front-end</a>
 </div>
 
-<div class="question">
-<p>
+<div class="question"><p>
 What is this <tt>__main()</tt> call that gets inserted into <tt>main()</tt>?
-</p>
-</div>
+</p></div>
 
 <div class="answer">
 <p>
@@ -426,10 +425,29 @@ The actual implementation of <tt>__main</tt> lives in the
 <tt>llvm/runtime/GCCLibraries/crtend/</tt> directory in the source-base, and is
 linked in automatically when you link the program.
 </p>
-
 </div>
 
+<!--=========================================================================-->
+
+<div class="question"><p>
+Where did all of my code go??
+</p></div>
 
+<div class="answer">
+<p>
+If you are using the LLVM demo page, you may often wonder what happened to all
+of the code that you typed in.  Remember that the demo script is running the
+code through the LLVM optimizers, so if you code doesn't actually do anything
+useful, it might all be deleted.
+</p>
+
+<p>
+To prevent this, make sure that the code is actually needed.  For example, if
+you are computing some expression, return the value from the function instead of
+leaving it in a local variable.  If you really want to constrain the optimizer,
+you can read from and assign to <tt>volatile</tt> global variables.
+</p>
+</div>
 
 <!-- *********************************************************************** -->
 <!-- *********************************************************************** -->