mirror of
https://github.com/openssl/openssl.git
synced 2024-12-21 06:09:35 +08:00
4e8c4b77ef
Reviewed-by: Tom Cosgrove <tom.cosgrove@arm.com> Reviewed-by: Tomas Mraz <tomas@openssl.org> (Merged from https://github.com/openssl/openssl/pull/24173)
34 lines
835 B
Markdown
34 lines
835 B
Markdown
Notes on ANSI C
|
|
===============
|
|
|
|
When building for pure ANSI C (C89/C90), you must configure with at least
|
|
the following configuration settings:
|
|
|
|
- `no-asm`
|
|
|
|
There are cases of `asm()` calls in our C source, which isn't supported
|
|
in pure ANSI C.
|
|
|
|
- `no-secure-memory`
|
|
|
|
The secure memory calls aren't supported with ANSI C.
|
|
|
|
- `-D_XOPEN_SOURCE=1`
|
|
|
|
This macro enables the use of the following types, functions and global
|
|
variables:
|
|
|
|
- `timezone`
|
|
|
|
- `-D_POSIX_C_SOURCE=200809L`
|
|
|
|
This macro enables the use of the following types, functions and global
|
|
variables:
|
|
|
|
- `ssize_t`
|
|
- `strdup()`
|
|
|
|
It's arguable that with gcc and clang, all of these issues are removed when
|
|
defining the macro `_DEFAULT_SOURCE`. However, that effectively sets the C
|
|
language level to C99, which isn't ANSI C.
|