cflags.SH - add commentary

Add comments to the top of cflags.SH to explain what it does.
Also make it output comments at the top of the generated cflags
script explaining that its auto-generated.

diff --git a/cflags.SH b/cflags.SH
index a80eb5d6eaac2a25d7d0c646690a583403f263f8..84e3187f028980db4b81d2c566437db27127b858 100755 (executable)
--- a/cflags.SH
+++ b/cflags.SH
@@ -1,5 +1,17 @@
 #!/bin/sh
 
+# Generate the cflags script, which is used to determine what cflags
+# to pass to the compiler.
+# We create a temporary test c program and repeatedly compile it with
+# various candidate flags, and from the compiler output, determine what
+# flags are supported.
+# From this we initialise the following variables in the cflags script:
+#
+#   $warn
+#   $stdflags
+#   $extra
+#   $_exe
+
 case $PERL_CONFIG_SH in
 '')
        if test -f config.sh; then TOP=.;
@@ -210,6 +222,11 @@ rm -f cflags
 $spitshell >cflags <<!GROK!THIS!
 $startsh
 
+# !!!!!!!   DO NOT EDIT THIS FILE   !!!!!!!
+
+# This file is generated by cflags.SH
+
+
 # Extra warnings, used e.g. for gcc.
 warn="$warn"
 # Extra standardness.