[PATCH 2/3 V2] [PATCH] checkpatch: Add error on use of attribute((weak)) or __weak declarations

[Joe Perches <joe@perches.com>]

Using weak declarations can have unintended link defects.
Emit an error on its use.

Signed-off-by: Joe Perches <joe@perches.com>
---
Maybe you prefer this.
It only warns on declarations.

 scripts/checkpatch.pl | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 696254e..8a577aa 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -4671,6 +4671,15 @@ sub process {
 			}
 		}
 
+# Check for __attribute__ weak, or __weak declarations (may have link issues)
+		if ($^V && $^V ge 5.10.0 &&
+		    $line =~ /(?:$Declare|$DeclareMisordered)\s*$Ident\s*$balanced_parens\s*(?:$Attribute)?\s*;/ &&
+		    ($line =~ /\b__attribute__\s*\(\s*\(.*\bweak\b/ ||
+		     $line =~ /\b__weak\b/)) {
+			ERROR("WEAK_DECLARATION",
+			      "Using weak declarations can have unintended link defects\n" . $herecurr);
+		}
+
 # check for sizeof(&)
 		if ($line =~ /\bsizeof\s*\(\s*\&/) {
 			WARN("SIZEOF_ADDRESS",
-- 
2.1.0