All of lore.kernel.org
 help / color / mirror / Atom feed
From: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
To: Linux-Sparse <linux-sparse@vger.kernel.org>
Cc: Christopher Li <sparse@chrisli.org>,
	Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Subject: [PATCH] Fix size calculation of unsized bool array
Date: Thu,  7 Jan 2016 02:47:09 +0100	[thread overview]
Message-ID: <1452131229-29756-1-git-send-email-luc.vanoostenryck@gmail.com> (raw)

This stops sparse from issuing the error message
	"error: cannot size expression"
for code like:
	static _Bool boolarray[] = {
		0,
		1,
	};
	static int n = sizeof(boolarray);

The fix consists of using array_element_offset() for calculating
the size of unsized arrays, like it is done elsewhere for sized ones.

Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
---
 symbol.c                |  2 +-
 validation/bool-array.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+), 1 deletion(-)
 create mode 100644 validation/bool-array.c

diff --git a/symbol.c b/symbol.c
index 0ceff628..92a7a625 100644
--- a/symbol.c
+++ b/symbol.c
@@ -393,7 +393,7 @@ static struct symbol * examine_node_type(struct symbol *sym)
 			int count = count_array_initializer(node_type, initializer);
 
 			if (node_type && node_type->bit_size >= 0)
-				bit_size = node_type->bit_size * count;
+				bit_size = array_element_offset(node_type->bit_size, count);
 		}
 	}
 	
diff --git a/validation/bool-array.c b/validation/bool-array.c
new file mode 100644
index 00000000..6c4c8723
--- /dev/null
+++ b/validation/bool-array.c
@@ -0,0 +1,47 @@
+static _Bool boolarray_d1[1];
+static _Bool boolarray_d8[8];
+static _Bool boolarray_i2[2] = {
+	0,
+	1,
+};
+static int nd1 = sizeof(boolarray_d1);
+static int nd8 = sizeof(boolarray_d8);
+static int ni2 = sizeof(boolarray_i2);
+
+
+static long longarray_u2[] = {
+	0,
+	1,
+};
+static int nl2 = sizeof(longarray_u2);
+
+/*
+ * Used to get "warning: excessive elements in array initializer"
+ * for all elements but the first one.
+ * Note: only occurs if nbr of elements is a multiple of 8
+ *       (if not, theer was another problem)
+ */
+static _Bool boolarray_u8[] = {
+	0,
+	1,
+	0,
+	1,
+	0,
+	1,
+	0,
+	1,
+};
+
+/*
+ * Used to get "error: cannot size expression" for the sizeof.
+ */
+static _Bool boolarray_u2[] = {
+	0,
+	1,
+};
+static int nu2 = sizeof(boolarray_u2);
+
+/*
+ * check-name: sizeof(bool array)
+ * check-command: sparse -Wno-sizeof-bool $file
+ */
-- 
2.7.0


             reply	other threads:[~2016-01-07  1:48 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-01-07  1:47 Luc Van Oostenryck [this message]
2016-02-04 16:10 ` [PATCH] Fix size calculation of unsized bool array Christopher Li

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1452131229-29756-1-git-send-email-luc.vanoostenryck@gmail.com \
    --to=luc.vanoostenryck@gmail.com \
    --cc=linux-sparse@vger.kernel.org \
    --cc=sparse@chrisli.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.