<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> <meta name="Generator" content="Microsoft Exchange Server">  <style></style> </head> <body> <font face="Calibri" size="2"><span style="font-size:11pt;"> <div>Hi,</div> <div> </div> <div>I was trying to enable the “stack smashing protection” for node.js(issue <a href="https://github.com/nodejs/node/issues/20928"><font color="#0563C1"><u>20928</u></font></a>). And I switched it on using “-fstack-protector”</div> <div>And made a benchmark test, while the result is quite strange. Then I found on my Ubuntu 16.04, the –fstack-protector-strong</div> <div>Was by default enabled. I checked it using the command:</div> <div><font face="Times New Roman"> </font></div> <div>Gcc –Q –v main.c</div> <div> </div> <div>And found the –fstack-protector-strong flag was listed inside the “options passed” by default.</div> <div><font face="Times New Roman"> </font></div> <div>So based on these, I have some questions:</div> <ol style="margin:0;padding-left:36pt;"> <li>I installed gcc from apt-get by default, is Ubuntu providing a customized version of GCC?</li><li>If answer of 1 is yes, then you may have a repo that host the customized GCC code, if I am right, could you please show me where I can find the proof of that customization?</li></ol> <div style="padding-left:36pt;">That would be much appreciated. <font face="Wingdings">J</font> Or if you can’t find the right code, can you show me where I can find the repo, then I can traverse the code and history to find the proof myself.</div> <div><font face="Times New Roman"> </font></div> <div>Below is my env:</div> <div>Ubuntu 16.04</div> <div>Gcc: 5.4.0-6ubuntu1~16.04.9</div> <div>CPU: <font face="Segoe UI" size="2" color="#24292E"><span style="font-size:10.5pt;">Intel(R) Core(TM) i7-4790 CPU @ 3.60GH</span></font><font face="Segoe UI" size="2" color="#24292E"><span style="font-size:10.5pt;">z</span></font><font face="Segoe UI" size="2" color="#24292E"><span style="font-size:10.5pt;"> x86_64</span></font></div> <div><font face="Times New Roman"> </font></div> <div>Thanks with regards,</div> <div>Shaoting</div> <div><font face="Times New Roman"> </font></div> </span></font> </body> </html>