Hello,
I have same problem.
I configured the Tools -> Configure "Build Lazarus" to have Clean + build on IDE, and it did not work for me.
Next I defined the "Clean up + Build all" predefined build "process". After that the IDE did not start, because It was stuck with some Example project ("Form resource TForm1 not found. For resourceless forms CreateNew constructor must be used. See the global variable RequireDerivedFormResource."). And Lazarus.exe don't have an Icon, so maybe something went wrong.
Restored the Old Lazarus.exe and it starts up.
Next with Optimized IDE, with the Clean+Build option on the IDE, lets see what that brings to me
OK... Now it works,
I had to also do : Run -> Clean up build files... And after that it woudl compile it.
Hope this rambling of mine solves the problem from someone else
Thanks for the tips!!!
-Tee-