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/* This checks if enums needing 8 bit but only having positive
values are correctly zero extended (instead of sign extended)
when stored into/loaded from a 8 bit bit-field of enum type (which
itself is implementation defined, so isn't necessarily supported by all
other compilers). */
enum tree_code {
SOME_CODE = 148, /* has bit 7 set, and hence all further enum values as well */
LAST_AND_UNUSED_TREE_CODE
};
typedef union tree_node *tree;
struct tree_common
{
union tree_node *chain;
union tree_node *type;
enum tree_code code : 8;
unsigned side_effects_flag : 1;
};
union tree_node
{
struct tree_common common;
};
enum c_tree_code {
C_DUMMY_TREE_CODE = LAST_AND_UNUSED_TREE_CODE,
STMT_EXPR,
LAST_C_TREE_CODE
};
enum cplus_tree_code {
CP_DUMMY_TREE_CODE = LAST_C_TREE_CODE,
AMBIG_CONV,
LAST_CPLUS_TREE_CODE
};
extern int printf(const char *, ...);
int blah(){return 0;}
int convert_like_real (tree convs)
{
switch (((enum tree_code) (convs)->common.code))
{
case AMBIG_CONV: /* This has bit 7 set, which must not be the sign
bit in tree_common.code, i.e. the bitfield must
be somehow marked unsigned. */
return blah();
default:
break;
};
printf("unsigned enum bit-fields broken\n");
}
int main()
{
union tree_node convs;
convs.common.code = AMBIG_CONV;
convert_like_real (&convs);
return 0;
}
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