Copter V3.1 Won’t Compile

I needed to lower the AUTO_YAW_SLEW_RATE parameter and tried to compile 3.1 but it told me that the generated binary was too long. V3.0.1 worked OK. I have the modified compiler (1.0.3) that I get last spring. Has their been any changes lately to the compiler? What am I doing wrong? I am running Windows XP.

V3.0.1
Binary sketch size: 234,668 bytes (of a 258,048 byte maximum)

V3.1
Binary sketch size: 262,408 bytes (of a 258,048 byte maximum)

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you need to install gcc 4.7.3 to be able to build the code small enough for APM2.5 with the current selected feature set,.

More details on how tools for each OS and how to build are here dev.ardupilot.com/wiki/building-the-code/