Visual Studio 2008 (C++): Why am I getting compiler warnings?

Question

I am getting Visual Studio compiler warnings from third-party includes and my coworker is not. The following are true:

• We have checked out the exact same code, .vcproj files, and .sln files, with no local modifications.
• We are including the exact same third-party files.
• We are using the exact same version of Visual Studio.
• We have both deleted all temporary (.user, .suo) files.

Can anybody offer an explanation for how this could be happening?

Or, if anyone can give me advice on how to directly eliminate the warnings, that'd be just as good. I've tried the obvious "Disable Specific Warnings" option in Properties > Configuration Properties > C/C++ > Advanced, and I've tried #pragma, to no avail.

Answer 1

Even if you're using the same project files it's possible to use different include directories because of the 'global' setting for "VC++ Directories" in the Tools/Options dialog.

Look at the BuildLog.htm file file that a build generates for any differences in details. Also, the /showIncludes option can be informative ("C/C++"/Advanced/"Show Includes" in the IDE's project settings).

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Edit:

Based on your comment that the warnings are C4244, it sounds like one of the following:

• one of you is building for x64 and the other is building for x86
• one of you has /Wp64 set
• one of you has a different warning level than the other

Answer 2

With the warning error: are you both on the same architecture ?

If you are on a 32bits machine and he is on a 64bits machine, Visual Studio might automatically select the native representation of integers for your respective machines... and they might differ :/

Answer 3

Check Tools->Options->Projects & Solutions->VC++ Directories

Go through all the different options under the "Show directories for" pulldown

Are the directory lists the same?

Answer 4

In project soultion properties, select C/C++ > 'General' and try setting the 'Detect 64-bit Probabilty Issues' to 'No' if its not already by default for 32-bit complier. /Wp64 (Detect 64-Bit Portability Issues)

also, check which character set is selected in project defaults.

Answer 5

Check the build log. Visual Studio generates a full log of what was built, and with exactly which command line switches and flags.

Then check environment variables.

Either the compiler is different, the code is different, or the way the compiler is invoked (check build logs and environment vars) is different.