This dumps the predefined preprocessor macros
#!/bin/sh
-# src/tools/ccsym
-
-trap "rm -f /tmp/$$.*" 0 1 2 3 15
-cd /tmp
-cat >$$.c <
-extern int foo;
-EOF
-for i in `cc -v -c $$.c 2>&1`
-do
- case "$i" in
- -D*) echo "$i" | sed 's/^-D//';;
- -A*) echo "$i" | sed 's/^-A\(.*\)(\(.*\))/\1=\2/';;
- esac
-done
+# display gcc predefined preprocessor macros
+gcc -dM -E - < /dev/null