Category Archives: Bugs

Determinism Bugs, Part Two, Kernel32.dll

It was literally the day after I cracked the __FILE__ determinism bug that I hit a completely different build determinism issue. I was asked to investigate why the Chrome build number reported for Chrome crashes on Windows 11 was lagging … Continue reading

Posted in Bugs, Chromium, Computers and Internet, Investigative Reporting, Programming, Symbols | Tagged , , | 17 Comments

Two Deterministic Build Bugs

‘Twas the week before Christmas and I ran across a deterministic-build bug. And then another one. One was in Chromium, and the other was in Microsoft Windows. It seemed like a weird coincidence so I thought I’d write about both … Continue reading

Posted in Bugs, Chromium, Computers and Internet, Debugging, Programming | Tagged , , | 14 Comments

Finding Windows HANDLE leaks, in Chromium and others

Three years ago I found a 32 GB memory leak caused by CcmExec.exe failing to close process handles. That bug is fixed, but ever since then I have had the handles column in  Windows Task Manager enabled, just in case … Continue reading

Posted in Bugs, Code Reliability, Investigative Reporting, uiforetw, xperf | Tagged , | 18 Comments

The Easy Ones – Three Bugs Hiding in the Open

I write a lot about investigations into tricky bugs – CPU defects, kernel bugs, transient 4-GB memory allocations – but most bugs are not that esoteric. Sometimes tracking down a bug is as simple as paying attention to server dashboards, … Continue reading

Posted in Bugs, Code analysis, Code Reliability, Debugging, Floating Point, Linux, Performance | Tagged | 17 Comments

GDI leaks and the importance of luck

In May 2019 I was asked to look at a potentially serious Chrome bug. I initially misdiagnosed it as unimportant, thus wasting two valuable weeks, and when I rejoined the investigation it was the number one browser-process crash in Chrome’s … Continue reading

Posted in Bugs, Chromium, Debugging, Programming | Tagged | 25 Comments

Bugs I Got Other Companies to Fix in 2013

Over the course of a year I fix a lot of bugs – that’s part of my job. But I’m not going to write about that. Instead I want to write about bugs that I found in other companies’ code, … Continue reading

Posted in Bugs, Programming | Tagged , | 12 Comments

How to Report a VC++ Code-Gen Bug

My coworkers recently found a bug in the x64 code generated by Visual C++. This bug exists in VC++ 2010 to VC++ 2013 RC. We put in a workaround (the traditional one of disabling optimizations for the afflicted function) and … Continue reading

Posted in Bugs, Investigative Reporting, Programming, Visual Studio | Tagged , , | 10 Comments

The New WPA Xperf Trace Viewer–New Bugs and Old

Every Windows performance expert should be using xperf traces. My preferred viewer for xperf traces is WPA – Windows Performance Analyzer. However the Windows 8 version of this tool has a few bugs in its display of custom ETW events. … Continue reading

Posted in Bugs, xperf | Tagged , , | 3 Comments

Other Causes of Alt+Tab Problems

Now that I have an easy way to find and fix problems with Alt+Tab it becomes easier to identify culprits. Whenever Alt+Tab misbehaves – whenever the grid of programs goes behind the current Aero Peek window – I run AltTabFixOnce.exe … Continue reading

Posted in Bugs, Computers and Internet | Tagged , | 5 Comments

Alt+Tab Bug Worsened by IE 10, But Fix Found

Windows 7 has an annoying bug that causes alt+tab to malfunction for many people. This bug, previously discussed on this blog in Alt+Tab Depth Inversion Bug, causes the grid of programs to be partially or completely hidden, making it much … Continue reading

Posted in Bugs, Computers and Internet, Investigative Reporting | Tagged , | 64 Comments