+# If this is bash, turn off all aliases.
+test -n "$BASH_VERSION" && unalias -a
+
+# Note that when supporting $EXEEXT (transparently mapping from PROG_NAME to
+# PROG_NAME.exe), we want to support hyphen-containing names like test-acos.
+# That is part of the shell-selection test above. Why use aliases rather
+# than functions? Because support for hyphen-containing aliases is more
+# widespread than that for hyphen-containing function names.