When an array is initialized, it may be convenient to first
initialize all entries with some default value via the
'[a ... b]' notation and then override some of these entries
with a non-default value. Unfortunately, this, of course,
is not compatible with the default warning flag '-Woverride-init'.
Fix this by introducing an exception to the usual detection
of overlapping initializers which, only for what concerns this
warning, ignore an '[a ... b]' entry if:
- it is the first one
- it covers the whole range of the array.
If needed, the previous ehaviour can be restored by using a new
warning flag, disabled by default: '-Woverride-init-whole-range'.
Suggested-by: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@xxxxxxxxx>
---
expand.c | 13 +++++++++++--
lib.c | 1 +
lib.h | 1 +
validation/field-override.c | 30 ++++++------------------------
4 files changed, 19 insertions(+), 26 deletions(-)
diff --git a/expand.c b/expand.c
index 80699c4d6..e6928bdc4 100644
--- a/expand.c
+++ b/expand.c
@@ -925,10 +925,11 @@ static void sort_expression_list(struct expression_list **list)
sort_list((struct ptr_list **)list, compare_expressions);
}
-static void verify_nonoverlapping(struct expression_list **list)
+static void verify_nonoverlapping(struct expression_list **list, struct expression *expr)
{
struct expression *a = NULL;
unsigned long max = 0;
+ unsigned long whole = expr->ctype->bit_size;
struct expression *b;
if (!Woverride_init)
@@ -946,6 +947,14 @@ static void verify_nonoverlapping(struct expression_list **list)
return;
}
end = off + bit_range(b);
+ if (!a && !Woverride_init_whole_range) {
+ // If first entry is the whole range, do not let
+ // any warning about it (this allow to initialize
+ // an array with some default value and then override
+ // some specific entries).
+ if (off == 0 && end == whole)
+ continue;
+ }
if (end > max) {
max = end;
a = b;
@@ -1019,7 +1028,7 @@ static int expand_expression(struct expression *expr)
case EXPR_INITIALIZER:
sort_expression_list(&expr->expr_list);
- verify_nonoverlapping(&expr->expr_list);
+ verify_nonoverlapping(&expr->expr_list, expr);
return expand_expression_list(expr->expr_list);
case EXPR_IDENTIFIER:
diff --git a/lib.c b/lib.c
index b3b38a43f..95a4c461d 100644
--- a/lib.c
+++ b/lib.c
@@ -233,6 +233,7 @@ int Wold_initializer = 1;
int Wone_bit_signed_bitfield = 1;
int Woverride_init = 1;
int Woverride_init_all = 0;
+int Woverride_init_whole_range = 0;
int Wparen_string = 0;
int Wptr_subtraction_blows = 0;
int Wreturn_void = 0;
diff --git a/lib.h b/lib.h
index 265c5ec7f..134e56040 100644
--- a/lib.h
+++ b/lib.h
@@ -119,6 +119,7 @@ extern int Wold_initializer;
extern int Wone_bit_signed_bitfield;
extern int Woverride_init;
extern int Woverride_init_all;
+extern int Woverride_init_whole_range;
extern int Wparen_string;
extern int Wptr_subtraction_blows;
extern int Wreturn_void;
diff --git a/validation/field-override.c b/validation/field-override.c
index 5b77af73e..ec6987df7 100644
--- a/validation/field-override.c
+++ b/validation/field-override.c
@@ -75,15 +75,9 @@ field-override.c:2:10: warning: Initializer entry defined twice
field-override.c:6:10: also defined here
field-override.c:3:10: warning: Initializer entry defined twice
field-override.c:5:10: also defined here
-field-override.c:14:10: warning: Initializer entry defined twice
-field-override.c:15:10: also defined here
-field-override.c:14:10: warning: Initializer entry defined twice
-field-override.c:16:10: also defined here
-field-override.c:14:10: warning: Initializer entry defined twice
-field-override.c:17:10: also defined here
-field-override.c:14:10: warning: Initializer entry defined twice
+field-override.c:17:10: warning: Initializer entry defined twice
field-override.c:18:10: also defined here
-field-override.c:14:10: warning: Initializer entry defined twice
+field-override.c:17:10: warning: Initializer entry defined twice
field-override.c:19:10: also defined here
field-override.c:23:10: warning: Initializer entry defined twice
field-override.c:24:10: also defined here
@@ -95,25 +89,13 @@ field-override.c:26:10: warning: Initializer entry defined twice
field-override.c:27:10: also defined here
field-override.c:26:10: warning: Initializer entry defined twice
field-override.c:28:10: also defined here
-field-override.c:34:10: warning: Initializer entry defined twice
-field-override.c:35:10: also defined here
-field-override.c:34:10: warning: Initializer entry defined twice
+field-override.c:35:10: warning: Initializer entry defined twice
field-override.c:36:10: also defined here
-field-override.c:34:10: warning: Initializer entry defined twice
-field-override.c:37:10: also defined here
-field-override.c:34:10: warning: Initializer entry defined twice
+field-override.c:37:10: warning: Initializer entry defined twice
field-override.c:38:10: also defined here
-field-override.c:34:10: warning: Initializer entry defined twice
+field-override.c:37:10: warning: Initializer entry defined twice
field-override.c:39:10: also defined here
-field-override.c:34:10: warning: Initializer entry defined twice
+field-override.c:37:10: warning: Initializer entry defined twice
field-override.c:40:10: also defined here
-field-override.c:62:10: warning: Initializer entry defined twice
-field-override.c:63:10: also defined here
-field-override.c:62:10: warning: Initializer entry defined twice
-field-override.c:65:10: also defined here
-field-override.c:62:10: warning: Initializer entry defined twice
-field-override.c:66:10: also defined here
-field-override.c:62:10: warning: Initializer entry defined twice
-field-override.c:64:10: also defined here
* check-error-end
*/
--
2.11.1
--
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