Warning when preprocessing conditionals

In case in a `#if` statement a space in the use of a macro is present a warning of the type:
    warning: preprocessing issue while doing constant expression evaluation: syntax error
is given. Removing the white space after an ID solves the issue

In the following the first expressing gives a warning whilst the second expression doesn't:
#if (!__GNUC_PREREQ (4, 6))
  int i0;
#endif
#if (!__GNUC_PREREQ(4, 6))
  int k0;
#endif

0 files changed, 0 insertions, 0 deletions