Compiler warning

[saleyn]

Describe the bug

In OTP-26 compilation of a NIF that includes <erl_nif.h> produces a warning:

$ cc -g -O3 -ansi -pedantic -Wall -Wextra -I../ -I ~/.asdf/installs/erlang/26.0/erts-14.0/include -fPIC -shared -o test.so test.c
In file included from test.c:4:
~/.asdf/installs/erlang/26.0/erts-14.0/include/erl_nif.h:192:21: warning: comma at end of enumerator list [-Wpedantic]
  192 |     ERL_NIF_UTF8 = 2,
      |                     ^

While the enum syntax permits the comma at the end of the last enum value, apparently the recent C compiler still emits the warning

File: erl_nif.h

typedef enum
{
    ERL_NIF_LATIN1 = 1,
    ERL_NIF_UTF8 = 2,                  // <--- here
}ErlNifCharEncoding;

[attah]

That's due to your -ansi flag (and being pedantic about that), not compilers in general.
Trailing comma was added in C99.
However; since C++ was slower at adding it (C++11?) it would make sense to not have it unless you already have somewhat high minimum C/C++ versions already elsewhere.

[saleyn]

I believe it complains when using the -pedantic compiler flag. But combining -pedantic -std=c99 seems to quiet the warning.

[attah]

Yes, pedantic ansi (aka c89) - as opposed to pedantic c99.