| Message ID | alpine.LFD.2.11.1403301020530.16374@i7.linux-foundation.org (mailing list archive) |
|---|---|
| State | Mainlined, archived |
| Headers | show |
On Sun, Mar 30, 2014 at 10:22 AM, Linus Torvalds <torvalds@linux-foundation.org> wrote: > > From: Linus Torvalds <torvalds@linux-foundation.org> > Date: Sun, 30 Mar 2014 10:13:54 -0700 > Subject: [PATCH 2/2] Use any previous initializer to size a symbol > > When we size a symbol, we only have one initializer per symbol, but we > may have multiple symbol declarations for the same symbol. So make sure > to walk the "same_symbol" chain to find the initializer, rather than > assuming it is attached to the current declaration. > > Reported-by: Hans Verkuil <hverkuil@xs4all.nl> > Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> This patch looks good to me. Will apply. > --- > > This seems to be the simplest approach. Chris, what was your concern about > scoping? The "same_symbol" list should already take scoping into account. This bug is a special case of the more general sparse bug in merging declaration types. The scoping I am concern about is some thing like this: (BTW, your patch does not have the scoping issue). extern void foo(void) __attribute__((X)); for (;;) { extern void foo(void) __attribute__((Y)); /* function foo() should have both attribute X and Y here */ } /* foo() should have only attribute X here */ Merging the initializer is a special case of this more general bug. Obviously, this patch fix the merging of initialization, should be applied. Chris -- To unsubscribe from this list: send the line "unsubscribe linux-sparse" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/symbol.c b/symbol.c index eb6e1215ee87..4b91abd8021e 100644 --- a/symbol.c +++ b/symbol.c @@ -354,6 +354,15 @@ static int count_array_initializer(struct symbol *t, struct expression *expr) return nr; } +static struct expression *get_symbol_initializer(struct symbol *sym) +{ + do { + if (sym->initializer) + return sym->initializer; + } while ((sym = sym->same_symbol) != NULL); + return NULL; +} + static struct symbol * examine_node_type(struct symbol *sym) { struct symbol *base_type = examine_base_type(sym); @@ -376,12 +385,15 @@ static struct symbol * examine_node_type(struct symbol *sym) sym->ctype.alignment = alignment; /* Unsized array? The size might come from the initializer.. */ - if (bit_size < 0 && base_type->type == SYM_ARRAY && sym->initializer) { - struct symbol *node_type = base_type->ctype.base_type; - int count = count_array_initializer(node_type, sym->initializer); - - if (node_type && node_type->bit_size >= 0) - bit_size = node_type->bit_size * count; + if (bit_size < 0 && base_type->type == SYM_ARRAY) { + struct expression *initializer = get_symbol_initializer(sym); + if (initializer) { + struct symbol *node_type = base_type->ctype.base_type; + int count = count_array_initializer(node_type, initializer); + + if (node_type && node_type->bit_size >= 0) + bit_size = node_type->bit_size * count; + } } sym->bit_size = bit_size;