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<div class="moz-cite-prefix">On 2013-07-20 18:25, David Blaikie
wrote:<br>
</div>
<blockquote
cite="mid:CAENS6EvxqJ_KmYLsEqZjRdT+uX7dcSh8T=yqM-2PUc95fvjWEg@mail.gmail.com"
type="cite">
<pre wrap="">On Sat, Jul 20, 2013 at 10:01 AM, Sian Mountbatten
<a class="moz-txt-link-rfc2396E" href="mailto:poenikatu@fastmail.co.uk"><poenikatu@fastmail.co.uk></a> wrote:
</pre>
<blockquote type="cite">
<pre wrap="">On 2013-07-20 17:44, David Blaikie wrote:
Nothing obviously wrong with that - yes, jumping in with a debugger
might be an option, but the code looks simple enough that I'd wonder
if it's an issue with linking or the standard library.
On Sat, Jul 20, 2013 at 6:46 AM, Sian Mountbatten
<a class="moz-txt-link-rfc2396E" href="mailto:poenikatu@fastmail.co.uk"><poenikatu@fastmail.co.uk></a> wrote:
Dear List
If I compile the file main.cpp to regex using this command:
clang++ -g -std=c++11 -stdlib=libc++ -o regex main.cpp
I get no warnings, no errors, in fact no console output from clang++.
When the program is run, it produces "\w+\d*" on the console.
Now, if I compile with this command:
clang++ -g -std=c++11 -o main.o -c main.cpp
and then link with this command:
clang++ -g -stdlib=libc++ -o regex main.o
again, I get no output from clang++. Unfortunately, when the output
program is run, it fails with "Segmentation violation".
Again, I'm assuming you've invoked UB & the two different standard
libraries are just failing in different ways. Once we see the code,
that might change.
What does "UB" mean?
</pre>
</blockquote>
<pre wrap="">
Undefined Behavior ( a good read on the subject if Chris Lattner's 3
part series: <a class="moz-txt-link-freetext" href="http://blog.llvm.org/2011/05/what-every-c-programmer-should-know.html">http://blog.llvm.org/2011/05/what-every-c-programmer-should-know.html</a>
) - though from your example there's nothing obviously wrong that I
can see.
</pre>
</blockquote>
<br>
The code was lifted from Bjarne's book, so I'd be surprised if there
*was* anything wrong with it.<br>
Because I succeeded in compiling LLVM/Clang using the GNU C++
library, I am now trying to<br>
build LLVM/Clang (svn rev. 186765) using the already compiled
Clang++ and libc++. We shall<br>
see if that succeeds.<br>
<pre class="moz-signature" cols="72">--
Sian Mountbatten <<a class="moz-txt-link-abbreviated" href="http://www.poenikatu.co.uk">www.poenikatu.co.uk</a>>
Learning C++!!!
I'm an FSF member (10888)
Help us support software freedom! <a class="moz-txt-link-freetext" href="http://www.fsf.org/jf?referrer=10888">http://www.fsf.org/jf?referrer=10888</a>
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