checkpatch: warn on const char foo[] = "bar"; declarations

These declarations should generally be static const to avoid poor
compilation and runtime performance where compilers tend to initialize
the const declaration for every call instead of using .rodata for the
string.

Miscellanea:

 - Convert spaces to tabs for indentation in 2 adjacent checks

Link: http://lkml.kernel.org/r/10ea5f4b087dc911e41e187a4a2b5e79c7529aa3.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 377f373..93e84c9 100755 (executable)
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3890,14 +3890,23 @@ sub process {
                        WARN("STATIC_CONST_CHAR_ARRAY",
                             "static const char * array should probably be static const char * const\n" .
                                $herecurr);
-               }
+               }
+
+# check for initialized const char arrays that should be static const
+               if ($line =~ /^\+\s*const\s+(char|unsigned\s+char|_*u8|(?:[us]_)?int8_t)\s+\w+\s*\[\s*(?:\w+\s*)?\]\s*=\s*"/) {
+                       if (WARN("STATIC_CONST_CHAR_ARRAY",
+                                "const array should probably be static const\n" . $herecurr) &&
+                           $fix) {
+                               $fixed[$fixlinenr] =~ s/(^.\s*)const\b/${1}static const/;
+                       }
+               }
 
 # check for static char foo[] = "bar" declarations.
                if ($line =~ /\bstatic\s+char\s+(\w+)\s*\[\s*\]\s*=\s*"/) {
                        WARN("STATIC_CONST_CHAR_ARRAY",
                             "static char array declaration should probably be static const char\n" .
                                $herecurr);
-               }
+               }
 
 # check for const <foo> const where <foo> is not a pointer or array type
                if ($sline =~ /\bconst\s+($BasicType)\s+const\b/) {