During the Reconstruction of Paris, the Baron Haussmann gave specific instructions to the architects designing buildings along the boulevards:

The eaves had to be at a 45 degree angle.
Each building was to take up the entire block.
Each building had to have six floors.
The upper floor and the penultimate floor had to feature balconies running the entire length of the block.

Finally, the corners had to be ??? ... to avoid featuring sharp or straight angles.

What is the word, or words, I'm looking for here?