BaseTools: Reject trailing content after !else and !endif

The DSC parser accepts "!else if <expression>" as an unconditional
!else branch without evaluating the trailing condition. This can select
an unintended build branch instead of reporting the syntax error.

For example, the following incorrect syntax is currently accepted:

  !if $(MODE) == 1
    # Branch A
  !else if $(MODE) == 2
    # Branch B
  !endif

When MODE is 3, the parser treats the second directive as a plain !else
and selects branch B. Replacing it with "!elseif $(MODE) == 2" would
correctly select neither branch.

Reject trailing content after !else and !endif. When the first word
following !else is "if", suggest "!elseif <expression>" instead.
Trailing comments remain valid because they are removed before
directive parsing.

Cc: Fei Shen <shenfei@loongson.cn>
Signed-off-by: Dongyan Qian <qiandongyan@loongson.cn>

0 files changed, 0 insertions, 0 deletions