How does the molarity of a solution change on boiling off the solvent?

The dilution equation $$M\_1V\_2=M\_2V\_2$$ is an equation that can be used to calculate how adding water can impact the volume and molarity of a solution. So I was wondering if this equation would apply if you were to remove the amount of solvent through means such as boiling. 


For instance, suppose I have a $\pu{100 mL}$ solution of $\ce{HCl}$ that has water as its solvent and has a molarity of $\pu{3.0 M}$. Would the molarity become $\pu{6.0 M}$ if were to boil out $\pu{50 mL}$ of water of the solvent, or would it have a different $M$ value?


