This is not limited to debugging. I get similar behavior trying to run a project on Windows.

I looked at the gdb log when this happened and the program is correctly loaded but fails when
given the run command (with an unknown target exception). Running the project also fails.
I suspect that runtime libraries aren't found because the compiler path isn't in the path. I
think we need to add the compiler path directory when we run or debug a program.

I think this is a P1 on the project system because the ability to develop without either Cygwin
or MinGW directories in the user's path was intended to be a significant feature in this release.
But it doesn't work because runtime libraries aren't found.

See also http://www.netbeans.org/issues/show_bug.cgi?id=120836

Yes, it's the same core problem: path to environment (that's where the compilers are) is not added to run environment. I added the path(s) to the run environment and GdbLite needs to do the 
same. Here is the code I added:

                    // Append compilerset base to run path. (IZ 120836)
                    ArrayList<String> env1 = new ArrayList<String>();
                    String csname = ((MakeConfiguration) pae.getConfiguration()).getCompilerSet().getOption();
                    String csdirs = CompilerSetManager.getDefault().getCompilerSet(csname).getDirectory();
                    if (((MakeConfiguration)pae.getConfiguration()).getCompilerSet().getFlavor().equals(CompilerFlavor.MinGW.toString())) {
                        // Also add msys to path. Thet's where sh, mkdir, ... are.
                        String msysBase = CppUtils.getMSysBase();
                        if (msysBase != null && msysBase.length() > 0) {
                            csdirs = csdirs + File.pathSeparator + msysBase + File.separator + "bin"; // NOI18N
                        }
                    }
                    boolean gotpath = false;
                    String pathname = Path.getPathName() + '=';
                    int i;
                    for (i = 0; i < env.length; i++) {
                        if (env[i].startsWith(pathname)) {
                            env1.add(env[i] + File.pathSeparator + csdirs); // NOI18N
                            gotpath = true;
                        } else {
                            env1.add(env[i]);
                        }
                    }
                    if (!gotpath) {
                        env1.add(pathname + Path.getPathAsString() + File.pathSeparator + csdirs);
                    }
                    env = env1.toArray(new String[env1.size()]);

GdbLite needs to add some similar code where it handles the debug environment. Reassigning to Gordon.

Note: I found (and fixed) a bug in CppUtils.getMSysBase. It didn't work on (my) Vista. I changed the logic so it looks for ':' and not '\t'. There are no tabs in the 
value on my Vista! You should double check that getCygwinBase and getMinGWBase also work on Vista. They seems to have been coded after the same 
pattern as getMSysBase.

Changing back to gdb subcat, since thats where the fix needs to be.

Created attachment 59636 [details]
Patch containing the fix

Fixed in trunk and the patch is attached. QA please verify the patch works so I can
integrate into release61.

verified in trunk 200804040003

Fixed in trunk with http://hg.netbeans.org/main?cmd=changeset;node=b89dc7d05d97.
Fixed in release61 with http://hg.netbeans.org/release61/rev/d16e512b86ca.

verified in NB6.1RC1 (build 200804082140)