Currently, sparse handles arrays of bools incorrectly. If you declare an
array of bools like this:
static _Bool boolarray[3] = {
[0] = 1,
[1] = 1,
};
...you get warnings like this (which are bogus):
./test.c:2:10: warning: Initializer entry defined twice
./test.c:3:10: also defined here
The problem is that bits_to_bytes rounds down instead of up, and sparse
defaults to _Bool being only 1 bit in size. This causes sparse to think
that they sit within the same byte, when they do not.
Fix bits_to_bytes to round up instead of down, and fix the call in
init_ctype to no longer correct for it. Also add a validation
test to ensure that we don't break this in the future.
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxxxxxxx>
---
symbol.c | 2 +-
target.h | 2 +-
validation/initializer-entry-defined-twice.c | 10 ++++++++++
3 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/symbol.c b/symbol.c
index eb6e1215ee87..f02e07bd8c59 100644
--- a/symbol.c
+++ b/symbol.c
@@ -888,7 +888,7 @@ void init_ctype(void)
struct symbol *sym = ctype->ptr;
unsigned long bit_size = ctype->bit_size ? *ctype->bit_size : -1;
unsigned long maxalign = ctype->maxalign ? *ctype->maxalign : 0;
- unsigned long alignment = bits_to_bytes(bit_size + bits_in_char - 1);
+ unsigned long alignment = bits_to_bytes(bit_size);
if (alignment > maxalign)
alignment = maxalign;
diff --git a/target.h b/target.h
index 1030c7c38993..140df3c1a64d 100644
--- a/target.h
+++ b/target.h
@@ -49,7 +49,7 @@ extern int enum_alignment;
static inline int bits_to_bytes(int bits)
{
- return bits >= 0 ? bits / bits_in_char : -1;
+ return bits >= 0 ? (bits + bits_in_char - 1) / bits_in_char : -1;
}
static inline int bytes_to_bits(int bytes)
diff --git a/validation/initializer-entry-defined-twice.c b/validation/initializer-entry-defined-twice.c
index 968e3dd1af2a..8a5bd3a95631 100644
--- a/validation/initializer-entry-defined-twice.c
+++ b/validation/initializer-entry-defined-twice.c
@@ -41,6 +41,16 @@ static struct same_offset not_an_error = {
.field1 = { },
.field2 = 0
};
+
+/*
+ * _Bools generally take a whole byte, so ensure that we can initialize
+ * them without spewing a warning.
+ */
+static _Bool boolarray[3] = {
+ [0] = 1,
+ [1] = 1,
+};
+
/*
* check-name: Initializer entry defined twice
*
--
1.9.3
--
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