+: check for void type
+echo " "
+echo "Checking to see how well your C compiler groks the void type..." >&4
+case "$voidflags" in
+'')
+ $cat >try.c <<'EOCP'
+#if TRY & 1
+void sub() {
+#else
+sub() {
+#endif
+ extern void moo(); /* function returning void */
+ void (*goo)(); /* ptr to func returning void */
+#if TRY & 8
+ void *hue; /* generic ptr */
+#endif
+#if TRY & 2
+ void (*foo[10])();
+#endif
+
+#if TRY & 4
+ if(goo == moo) {
+ exit(0);
+ }
+#endif
+ exit(0);
+}
+int main() { sub(); }
+EOCP
+ if $cc $ccflags -c -DTRY=$defvoidused try.c >.out 2>&1 ; then
+ voidflags=$defvoidused
+ echo "Good. It appears to support void to the level $package wants.">&4
+ if $contains warning .out >/dev/null 2>&1; then
+ echo "However, you might get some warnings that look like this:"
+ $cat .out
+ fi
+ else
+echo "Hmm, your compiler has some difficulty with void. Checking further..." >&4
+ if $cc $ccflags -c -DTRY=1 try.c >/dev/null 2>&1; then
+ echo "It supports 1..."
+ if $cc $ccflags -c -DTRY=3 try.c >/dev/null 2>&1; then
+ echo "It also supports 2..."
+ if $cc $ccflags -c -DTRY=7 try.c >/dev/null 2>&1; then
+ voidflags=7
+ echo "And it supports 4 but not 8 definitely."
+ else
+ echo "It doesn't support 4..."
+ if $cc $ccflags -c -DTRY=11 try.c >/dev/null 2>&1; then
+ voidflags=11
+ echo "But it supports 8."
+ else
+ voidflags=3
+ echo "Neither does it support 8."
+ fi
+ fi
+ else
+ echo "It does not support 2..."
+ if $cc $ccflags -c -DTRY=13 try.c >/dev/null 2>&1; then
+ voidflags=13
+ echo "But it supports 4 and 8."
+ else
+ if $cc $ccflags -c -DTRY=5 try.c >/dev/null 2>&1; then
+ voidflags=5
+ echo "And it supports 4 but has not heard about 8."
+ else
+ echo "However it supports 8 but not 4."
+ fi
+ fi
+ fi
+ else
+ echo "There is no support at all for void."
+ voidflags=0
+ fi
+ fi
+esac
+case "$voidflags" in
+"$defvoidused") ;;
+*) $cat >&4 <<'EOM'
+ Support flag bits are:
+ 1: basic void declarations.
+ 2: arrays of pointers to functions returning void.
+ 4: operations between pointers to and addresses of void functions.
+ 8: generic void pointers.
+EOM
+ dflt="$voidflags";
+ rp="Your void support flags add up to what?"
+ . ./myread
+ voidflags="$ans"
+ ;;
+esac
+$rm -f try.* .out
+
+: check for length of pointer
+echo " "
+case "$ptrsize" in
+'')
+ echo "Checking to see how big your pointers are..." >&4
+ if test "$voidflags" -gt 7; then
+ echo '#define VOID_PTR char *' > try.c
+ else
+ echo '#define VOID_PTR void *' > try.c
+ fi
+ $cat >>try.c <<'EOCP'
+#include <stdio.h>
+int main()
+{
+ printf("%d\n", (int)sizeof(VOID_PTR));
+ exit(0);
+}
+EOCP
+ set try
+ if eval $compile_ok; then
+ ptrsize=`$run ./try`
+ echo "Your pointers are $ptrsize bytes long."
+ else
+ dflt='4'
+ echo "(I can't seem to compile the test program. Guessing...)" >&4
+ rp="What is the size of a pointer (in bytes)?"
+ . ./myread
+ ptrsize="$ans"
+ fi
+ ;;
+esac
+$rm -f try.c try
+case "$use64bitall" in
+"$define"|true|[yY]*)
+ case "$ptrsize" in
+ 4) cat <<EOM >&4
+
+*** You have chosen a maximally 64-bit build, but your pointers
+*** are only 4 bytes wide, disabling maximal 64-bitness.
+
+EOM
+ use64bitall="$undef"
+ case "$use64bitint" in
+ "$define"|true|[yY]*) ;;
+ *) cat <<EOM >&4
+
+*** Downgrading from maximal 64-bitness to using 64-bit integers.
+
+EOM
+ use64bitint="$define"
+ ;;
+ esac
+ ;;
+ esac
+ ;;
+esac
+
+