Explicitly require C99 if using autoconf < 2.70.

This commit is contained in:
Martin Whitaker 2021-01-05 20:41:06 +00:00
parent ba25b55f53
commit 57e87149e8
1 changed files with 4 additions and 1 deletions

View File

@ -14,6 +14,8 @@ AC_CONFIG_HEADERS([tgt-pcb/pcb_config.h])
AC_CANONICAL_HOST
dnl Checks for programs.
AC_PROG_CC
AC_PREREQ([2.62])
m4_version_prereq([2.70], [], [AC_PROG_CC_C99])
AC_PROG_CXX
AC_PROG_RANLIB
AC_CHECK_TOOL(LD, ld, false)
@ -256,7 +258,8 @@ AC_CHECK_FUNCS(fopen64)
# The following math functions may be defined in the math library so look
# in the default libraries first and then look in -lm for them. On some
# systems we may need to use the compiler in C99 mode to get a definition.
# Modern versions of autoconf will enable C99 if it is available.
# autoconf >= 2.70 will enable C99 if it is available. For older autoconf
# versions, we requested C99 mode earlier with AC_PROG_CC_C99.
AC_SEARCH_LIBS([lround], [m], [AC_DEFINE([HAVE_LROUND], [1])])
AC_SEARCH_LIBS([llround], [m], [AC_DEFINE([HAVE_LLROUND], [1])])
AC_SEARCH_LIBS([nan], [m], [AC_DEFINE([HAVE_NAN], [1])])