调试时自动禁用 Visual Studio 断点

Question

I am running C++ code in VS 2012. I have set a simple Breakpoint

int main(int argc, char **argv)
{
    time_t start_time;
    time(&start_time);

    DUALISO_TIME dualiso_time;
    IO_TIME io_time = {0.0, 0.0};
    IO_INFO io_info;
    IJK::ERROR error;
    cout <<"DEBUG "<< endl;  // I have set a breakpoint.

While debugging the breakpoint briefly turns white (from red) but the debugger does not break at the break point, it just continues on. (The code is being run because it prints DEBUG in console.) I have searched for a while but I have not found any solution.

Some notes. The particular project is selected as the startUp Project. I have tried cleaning and re-building. The part of the code is definitely being run. I can even see the BreakPoint changing to white from red briefly, but the debugger is not stopping at the point. Here is SCREEN SHOT

Answer 1

Some reasons a breakpoint will not to be hit:

• The executable and the code do not match. For example, you changed the code, but the executable was in use when you compiled, and was not actually updated.
• The executable is running in Administrative mode, but Visual Studio is running as a regular user.
• Breakpoints can be disabled, but still exist. Go to the breakpoints window and be sure the breakpoint is enabled.

Answer 2

One extra reason, if you work with C# at least (not sure if exactly the same applies to C++ projects):

Your current build configuration is not configured to produce PDB files.

Go to your project, right click > Properties > Build > Advanced... > Debugging information .

Set that to full .

Answer 3

Here are some reasons that weren't mentioned already:

• macros can remove code in the preprocess phase
• optimizations . Some code can be optimised out. Use no optimizations in order to debug.

Answer 4

When the breakpoints are white that is the indication that Visual Studio is unable to match up the place in the source file with the application it is being debugged. Typically this occurs for the following reasons

• The source and executable are out of date. A full rebuild will often fix this
• The PDB files for the executable cannot be located. Go to Debug -> Windows -> Modules and make sure the PDB is correctly loaded

Answer 5

This can happen because of compiler optimizations. If you compiled with gcc -O then the program will be optimized and Visual Studio breakpoints will become disabled after attaching the program. To solve this, you can disable the compiler optimization with additional 0 following the -O like below.

gcc -O0

You can also use gcc -Og (available from gcc 4.8). This should allow both optimization and debugging.