+
+dnl ** figure out the alignment restriction of a type
+dnl (required SIZEOF test but AC_CHECK_SIZEOF doesn't call PROVIDE
+dnl so we can't call REQUIRE)
+
+dnl FPTOOLS_CHECK_ALIGNMENT(TYPE)
+AC_DEFUN(FPTOOLS_CHECK_ALIGNMENT,
+[changequote(<<, >>)dnl
+dnl The name to #define.
+define(<<AC_TYPE_NAME>>, translit(alignment_$1, [a-z *], [A-Z_P]))dnl
+dnl The cache variable name.
+define(<<AC_CV_NAME>>, translit(ac_cv_alignment_$1, [ *], [_p]))dnl
+dnl The name of the corresponding size.
+define(<<AC_CV_SIZEOF_NAME>>, translit(ac_cv_sizeof_$1, [ *], [_p]))dnl
+changequote([, ])dnl
+AC_MSG_CHECKING(alignment of $1)
+AC_CACHE_VAL(AC_CV_NAME,
+[AC_TRY_RUN([
+#include <stdio.h>
+#if HAVE_STDDEF_H
+#include <stddef.h>
+#endif
+#ifndef offsetof
+#define offsetof(ty,field) ((size_t)((char *)&((ty *)0)->field - (char *)(ty *)0))
+#endif
+int
+main()
+{
+ FILE *f=fopen("conftestval", "w");
+ if (!f) exit(1);
+ fprintf(f, "%d\n", offsetof(struct { char c; $1 ty;},ty));
+ exit(0);
+}],
+AC_CV_NAME=`cat conftestval`,
+AC_CV_NAME=$AC_CV_SIZEOF_NAME,
+AC_CV_NAME=$AC_CV_SIZEOF_NAME)])
+AC_MSG_RESULT($AC_CV_NAME)
+AC_DEFINE_UNQUOTED(AC_TYPE_NAME, $AC_CV_NAME)
+AC_PROVIDE($AC_TYPE_NAME)
+undefine([AC_TYPE_NAME])dnl
+undefine([AC_CV_NAME])dnl
+undefine([AC_CV_SIZEOF_NAME])dnl
+])
+
+dnl ** figure out whether C compiler supports 'long long's
+dnl (Closely based on Andreas Zeller's macro for testing
+dnl for this under C++)
+dnl
+dnl If the C compiler supports `long long' types,
+dnl define `HAVE_LONG_LONG'.
+dnl
+AC_DEFUN(FPTOOLS_C_LONG_LONG,
+[
+AC_REQUIRE([AC_PROG_CC])
+AC_MSG_CHECKING(whether ${CC} supports long long types)
+AC_CACHE_VAL(fptools_cv_have_long_long,
+[
+AC_LANG_SAVE
+AC_LANG_C
+AC_TRY_COMPILE(,[long long a;],
+fptools_cv_have_long_long=yes,
+fptools_cv_have_long_long=no)
+AC_LANG_RESTORE
+])
+AC_MSG_RESULT($fptools_cv_have_long_long)
+if test "$fptools_cv_have_long_long" = yes; then
+AC_DEFINE(HAVE_LONG_LONG)
+fi
+])
+
+dnl *** Can we open files in binary mode? ***
+dnl
+AC_DEFUN(FPTOOLS_O_BINARY,
+[
+AC_REQUIRE([AC_PROG_CC])
+AC_MSG_CHECKING(whether we can open files in binary mode)
+AC_CACHE_VAL(fptools_cv_have_o_binary,
+[
+AC_LANG_SAVE
+AC_LANG_C
+AC_TRY_COMPILE(,
+[#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+int x = O_BINARY;],
+fptools_cv_have_o_binary=yes,
+fptools_cv_have_o_binary=no)
+AC_LANG_RESTORE
+])
+AC_MSG_RESULT($fptools_cv_have_o_binary)
+if test "$fptools_cv_have_o_binary" = yes; then
+AC_DEFINE(HAVE_O_BINARY)
+fi
+])
+
+dnl *** Which one comes first, .text or .data? ***
+dnl
+AC_DEFUN(FPTOOLS_CODE_BEFORE_DATA,
+[AC_CACHE_CHECK([if code section appears before data], fptools_cv_code_bef_data,
+[AC_TRY_RUN([
+int f() { return 1; }
+int i;
+int main() { return ((char*)&f > (char*)&i); }
+
+],
+fptools_cv_code_bef_data=yes, fptools_cv_code_bef_data=no)])
+if test "$fptools_cv_code_bef_data" = yes; then
+ AC_DEFINE(CODE_BEFORE_DATA)
+fi
+])
+
+dnl *** Helper function **
+dnl
+AC_DEFUN(FPTOOLS_IN_SCOPE,AC_TRY_LINK([extern char* $1;],[return (int)&$2], $3=yes, $3=no))
+
+dnl *** What's the end-of-text-section marker called? ***
+dnl
+AC_DEFUN(FPTOOLS_END_TEXT_SECTION,
+[AC_CACHE_CHECK([for end of text section marker], fptools_cv_end_of_text,
+[
+not_done=1
+for i in etext _etext __etext; do
+ FPTOOLS_IN_SCOPE($i,$i,fptools_cv_end_of_text)
+ if test "$fptools_cv_end_of_text" = yes; then
+ AC_DEFINE(TEXT_SECTION_END_MARKER, $i)
+ not_done=0
+ break
+ fi
+done
+if test "$not_done"; then
+FPTOOLS_IN_SCOPE(etext asm("etext"),etext,fptools_cv_end_of_text);
+if test "$fptools_cv_end_of_text" = yes; then
+ AC_DEFINE(TEXT_SECTION_END_MARKER, etext asm("etext"))
+else
+ AC_DEFINE(TEXT_SECTION_END_MARKER, dunno_what_it_is)
+fi
+fi
+])])
+
+dnl *** What's the end-of-data-section marker called? ***
+dnl
+AC_DEFUN(FPTOOLS_END_DATA_SECTION,
+[AC_CACHE_CHECK([for end of data section marker], fptools_cv_end_of_data,
+[
+not_done=1
+for i in end _end __end; do
+ FPTOOLS_IN_SCOPE($i,$i,fptools_cv_end_of_data)
+ if test "$fptools_cv_end_of_data" = yes; then
+ AC_DEFINE(DATA_SECTION_END_MARKER, $i)
+ not_done=0
+ break
+ fi
+done
+if test "$not_done"; then
+FPTOOLS_IN_SCOPE(end asm("end"),end,fptools_cv_end_of_data);
+if test "$fptools_cv_end_of_data" = yes; then
+ AC_DEFINE(DATA_SECTION_END_MARKER, end asm("end"))
+else
+ AC_DEFINE(DATA_SECTION_END_MARKER, dunno_what_it_is)
+fi
+fi
+])])