When baking an image in 32 bit Float in Cycles or Blender render instead of baking it automatically in Linear like the 8 bit image, Blender bakes it in sRGB so it's unusable by game engines. That's not the only problem, compositing it by fixing the gamma to convert it into Linear generates some artefacts worse than directly baking a 8 bit image.
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Bake sets raw pixel values. What's most likely happening here is that your 32bit image color space is set to Linear, which would apply Linear to sRGB conversion on display. To properly see your normal map you should set color space to Non-Color.
Thank you for the clarification. And yes if I set the image to Raw i see it displayed linearly but when i save it it's converted in sRGB i don't know why. Also if I bake in Raw and switch the color space and go back to raw it's displayed like the sRGB version.
Why am I experiencing this in Blender 2.78? Is this truly resolved?
EDIT: Nevermind, I misread the time stamp thinking this was resolved in 2010. I should update to 2.79 or the version of this commit.
Needed this to work correctly for some multi-layer normal map blending workflow for material authoring.