Re: [PATCH 2/2] parse-options: adjust `parse_opt_unknown_cb()`s declared return type
- From
Junio C Hamano <gitster@pobox.com>
- Date
- May 13, 2019, 23:29 UTC
- Message-ID
- <xmqqk1eu9bnf.fsf@gitster-ct.c.googlers.com>
- In-Reply-To
- <dd283736b72d3e52bd298b0360ab66ffd15c1cf9.1557787395.git.gitgitgadget@gmail.com>
"Johannes Schindelin via GitGitGadget" <gitgitgadget@gmail.com> writes:
Show 12 quoted lines
> From: Johannes Schindelin <johannes.schindelin@gmx.de> > > In f41179f16ba2 (parse-options: avoid magic return codes, 2019-01-27), > the signature of the low-level parse-opt callback function was changed > to return an `enum`. > > And while the implementations were changed, one declaration was left > unchanged, still claiming to return `int`. > > This can potentially lead to problems, as compilers are free to choose > any integral type for an `enum` as long as it can represent all declared > values.
The enum is meant to represent "these magic negative numbers", and if the compiler chose "long" for it and the implementation of the function returned a "long", while the caller thought it would yield an "int", things will break.
Looks good to make callers' expectation and what callee does consistent.
Show 20 quoted lines
> > Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> > --- > parse-options.h | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/parse-options.h b/parse-options.h > index bd00cf0049..cd756833a9 100644 > --- a/parse-options.h > +++ b/parse-options.h > @@ -286,7 +286,9 @@ int parse_opt_commit(const struct option *, const char *, int); > int parse_opt_tertiary(const struct option *, const char *, int); > int parse_opt_string_list(const struct option *, const char *, int); > int parse_opt_noop_cb(const struct option *, const char *, int); > -int parse_opt_unknown_cb(struct parse_opt_ctx_t *ctx, const struct option *, const char *, int); > +enum parse_opt_result parse_opt_unknown_cb(struct parse_opt_ctx_t *ctx, > + const struct option *, > + const char *, int); > int parse_opt_passthru(const struct option *, const char *, int); > int parse_opt_passthru_argv(const struct option *, const char *, int);