- #pragma {} were used to match curly brackets with
  extern "C" {}, so that text editors would not indent
  the entire header file due to the surrounding { }s
- However this use of #pragma, when compiling with -Wall,
  generates a lot of "ignoring #pragma {}" warnings.
  These can be turned off, but this in turn might hide
  some other strange use of #pragma somewhere else.
- The replacement instead uses #if 0 to skip compiling
  the matching bracket, and should never generate warnings
Original: 2302493cc7ab927a589d2e7c59b7c5b72afafcf0