On Wed, 31 Aug 2022, Qing Zhao wrote: > Does the above mean that -std=gnu89 does not support C99 flexible array > member, then
No. Flexible array members are supported by GCC in all C standards modes. The C90 standard doesn't support them, but that's irrelevant to what GCC supports; it just means a diagnostic is required for strict conformance in pre-C99 modes. > When -std=gnu89 + -fstrict-flex-array=3 (ONLY C99 flexible array member > [] is treated as a valid flexible array) present together, That seems reasonable enough without a warning. If people want a warning for flexible array members in older language modes, they can use -pedantic; I don't think we need to warn for any particular -fstrict-flex-array modes there. -- Joseph S. Myers jos...@codesourcery.com
