Using braces everywhere is definitely good style, but it isn't a practical solution because there's a ton of existing C/C++ code that doesn't use braces.
It would make sure that no new errors are introduced due to this.
The compiler would need to require braces in new code, but allow brace-free style in old code; you'd need to integrate it with the source control system so it knows what code is new. Doable, but tricky.
- all new files are checked
- old files are put in a whitelist for the style checker, the submitter is supposed to remove the file from the whitelist when signifcant changes are made
It is good to hear others are doing it.
It is never an error to insert braces, and the rules for inserting braces are fully deterministic in C.