> 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
