cfm: fatal error: 'stdatomic.h' file not found

[ryandesign (Ryan Carsten Schmidt)]

cfm fails to build on Lion because it can't find the stdadomic.h header. See ​this log:

cc -O3 -std=c11 -Wall -W -pedantic -D_XOPEN_SOURCE=700 cfm.c -o cfm
cfm.c:19:10: fatal error: 'stdatomic.h' file not found
#include <stdatomic.h>
         ^
1 error generated.

Lion's clang is supposed to support C11, but ​apparently this header was missing until Xcode 7. You could combat this using:

PortGroup compiler_blacklist_versions 1.0

near the top of the Portfile after the PortSystem line, and

compiler.blacklist-append {clang < 700}

near the end of the file. However, compiler blacklisting will have no effect until the port is using the right compiler.

[ryandesign (Ryan Carsten Schmidt)]

In 3f10173a71f4d1d03e69b7d9e8b3d2d1c394060f/macports-ports (master):

cfm: Blacklist compilers without stdatomic.h

Closes: #60429