Hello,
as stated in the TODO file bitfields are buggy.
For example the following does not work:
struct{short x:12; char y:1;}s; s.y=1;
The attached patch improves bitfield handling.
With it the previous example gets fixed.
There are still corner cases which are still failing, like:
struct{int x:31; char y:2;}s; s.y=1;
in which the char overflows the 32-bit type.
Feel free to apply it to tcc.
Regards,
Vicente.
This patch improves bitfield handling, but the following still fails:
int main(){
struct {
int x:31; // long long int x:63;
char y: 2;
} s;
s.y = 1;
return s.y != 1;
}
--- a/tccgen.c
+++ b/tccgen.c
@@ -4811,6 +4811,11 @@ ST_FUNC void unary(void)
gen_op('+');
/* change type to field type, and set to lvalue */
vtop->type = s->type;
+ if (vtop->type.t & VT_BITFIELD) {
+ int dbt = vtop->type.t & VT_BTYPE;
+ if(dbt==VT_BOOL || dbt==VT_BYTE || dbt==VT_SHORT)
+ vtop->type.t = (vtop->type.t & ~VT_BTYPE) | VT_INT;
+ }
vtop->type.t |= qualifiers;
/* an array is never an lvalue */
if (!(vtop->type.t & VT_ARRAY)) {
_______________________________________________
Tinycc-devel mailing list
[email protected]
https://lists.nongnu.org/mailman/listinfo/tinycc-devel
