On Feb 5, 2021, at 9:51 AM, Todd C. Miller <Todd.Miller@xxxxxxx>
wrote:
On Fri, 05 Feb 2021 15:42:28 +0100, =?utf-8?Q?S=C3=A9bastien?=
Hinderer wrote:
It seems AC_PROG_CC wrongly believes clang is gcc and that may cause
problems
when clang is passed a warning which is only supposrted by gcc, as
is
the case e.g. for -Wno-stringop-truncation.
clang also defines __GNUC__ and the related defines, which is why
it is identified as gcc.
Is there a recommended way to determine for sure from a configure
script
whether the detected C compiler is clang or gcc?
I would *discourage* trying to figure out if a C compiler is gcc or
clang.
Instead, create separate detectors for whatever you’re looking for.
The gcc & clang groups coordinate with each other; they try to provide
the same
flags & API for the same functionality, and occasionally copy from each
other.
So trying to detect “do this if GCC” is generally wrong; clang may have
that interface & functionality
when someone compiles the code.
--- David A. Wheeler
