Xcode 4 warning: "could not find object file"

I am writing a C++ program in Xcode to carry out a calculation, linking to the GSL 1.15 and Eigen 3 libraries. My code builds successfully and gives me the correct values in Target Output mode. However, when I switch over to Debugger 开发者_Python百科Mode, there is a huge list of warnings of the form:

warning: Could not find object file "~/Documents/Research/gsl-1.15/.libs/version.o" - no debug information available for "version.c"."

What does this warning mean? How can I fix it?

Warnings in Xcode are sometimes useful, but sometimes just annoying. No debug information means that, you can not debug that file but you can copile it and it should work just fine.