AC_PREREQ([2.69])
AC_INIT([fastwc], [0.1.0], [], [fastwc])
AC_CONFIG_SRCDIR([src/main.c])

# Build flavor: --enable-glibc links dynamically against the system libc
# (respecting CC, whatever it is). The default is a fully static musl
# binary, preferring musl-gcc even when CC is set in the environment,
# since removing ld.so from startup is exactly what the tiny-file
# benchmark races hinge on.
AC_ARG_ENABLE([glibc],
  [AS_HELP_STRING([--enable-glibc],
    [link dynamically against the system libc (respects CC) instead of the default static musl])],
  [enable_glibc=$enableval], [enable_glibc=no])

STATIC_LDFLAGS=
if test "x$enable_glibc" = xno; then
  # Static musl is the default toolchain. Fall back to the system
  # compiler (dynamic link) only when no musl compiler is installed.
  AC_PATH_PROGS([MUSL_CC], [musl-gcc x86_64-linux-musl-gcc])
  if test -n "$MUSL_CC"; then
    CC="$MUSL_CC"
    STATIC_LDFLAGS="-static"
  fi
fi

AC_PROG_CC
AC_CHECK_TOOL([STRIP], [strip], [:])
AC_USE_SYSTEM_EXTENSIONS
AM_INIT_AUTOMAKE([foreign subdir-objects])

AS_IF([test "x$enable_glibc" = xyes],
  [AC_MSG_NOTICE([fastwc: glibc build requested, using $CC])],
  [AS_IF([test -n "$MUSL_CC"],
     [AC_MSG_NOTICE([fastwc: building against static musl ($MUSL_CC)])],
     [AC_MSG_WARN([fastwc: musl-gcc not found; falling back to $CC (dynamic link). Install a musl toolchain or configure --enable-glibc.])])])
AC_SUBST([STATIC_LDFLAGS])

AC_CONFIG_FILES([Makefile])
AC_OUTPUT