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PODisable "if(0)" elimination in gcc
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copied!<p>How can I prevent GCC from eliminating the code inside <strong>if(0)</strong> block?</p> <p>When I use Visual Studio, one of my debugging techniques is to put code like this in my program:</p> <pre><code>if (0) do_some_debug_printing_and_checking(); </code></pre> <p>Then, when a breakpoint is hit, I click at the <strong>do_some_debug_printing_and_checking()</strong> line, select "set next statement" and force it to execute.</p> <p>When I use gcc/gdb as a back-end, the "set next statement" does not work anymore, as GCC simply removes the code from inside the <strong>if(0)</strong> statement.</p> <p>I am of course using the <strong>-O0</strong> flag to disable optimization. I have also tried the <strong>-fno-dce -fno-tree-dce</strong> flags to disable dead code elimination explicitly, but it has no effect: the contents of <strong>if(0)</strong> is just not present in the binary file and I cannot use <strong>set next statement</strong> to jump into it.</p> <p>Is there any good way to tell gcc to disable elimination of <strong>if(0)</strong> contents?</p> <p>Edit:</p> <p>Thanks for the "additional variable" workaround, however there are 2 things I don't like about it:</p> <ol> <li>It's still an extra line of code</li> <li>It won't be automatically optimized out when I build the release version and do want those debug things to disappear. Surely I can use #ifdef-s, but that's even more extra lines.</li> </ol> <p>Really, there's absolutely no option to make GCC keep that dead code?</p>

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