configure.ac/CMake: Check for round() and stdbool.h
Not all the compilers that HarfBuzz is buildable on supports round() and
has the header stdbool.h, so we check for them and define HAVE_ROUND and
HAVE_STDBOOL_H repsectively in our CFLAGS so that we include them only
when they are found, or use fallback implementations when necessary.
Also include FindPythonInterp earlier as we need PYTHON_EXECUTABLE to be
set for running the tests.
diff --git a/configure.ac b/configure.ac
index 1fb8a10..031be4a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -78,8 +78,15 @@
])
# Functions, and headers
+
AC_CHECK_FUNCS(atexit mprotect sysconf getpagesize mmap isatty newlocale strtod_l setlinebuf)
-AC_CHECK_HEADERS(unistd.h sys/mman.h xlocale.h)
+
+save_libs="$LIBS"
+LIBS="$LIBS -lm"
+AC_CHECK_FUNCS([round], ,[AC_CHECK_DECLS([round], , ,[#include <math.h>])])
+LIBS="$save_libs"
+
+AC_CHECK_HEADERS(unistd.h sys/mman.h xlocale.h stdbool.h)
# Compiler flags
AC_CANONICAL_HOST
