OpenE2K/rust
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Check repr attribute consistency at check time, not translation.

Browse Source 
Note that raising an error during trans doesn't stop the compile or cause
rustc to exit with a failure status, currently, so this is of more than
cosmetic importance.
This commit is contained in:
Jed Davis 2013-08-29 23:45:06 -07:00
parent c8c08763ec
commit a027f164bc
3 changed files with 64 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
src/librustc/middle/trans/adt.rs
View File

@ -150,6 +150,8 @@ fn represent_type_uncached(cx: &mut CrateContext, t: ty::t) -> Repr {
if cases.len() == 0 {
// Uninhabitable; represent as unit
// (Typechecking will reject discriminant-sizing attrs.)
assert_eq!(hint, attr::ReprAny);
return Univariant(mk_struct(cx, [], false), false);
}
@ -165,13 +167,6 @@ fn represent_type_uncached(cx: &mut CrateContext, t: ty::t) -> Repr {
return mk_cenum(cx, hint, &bounds);
}
if cases.len() == 1 {
// Equivalent to a struct/tuple/newtype.
// FIXME: should this conflict with a discriminant size hint?
assert_eq!(cases[0].discr, 0);
return Univariant(mk_struct(cx, cases[0].tys, false), false)
}
// Since there's at least one
// non-empty body, explicit discriminants should have
// been rejected by a checker before this point.
@ -181,8 +176,15 @@ fn represent_type_uncached(cx: &mut CrateContext, t: ty::t) -> Repr {
ty::item_path_str(cx.tcx, def_id)))
}
if cases.len() == 2 {
// FIXME: disable if size hint present?
if cases.len() == 1 {
// Equivalent to a struct/tuple/newtype.
// (Typechecking will reject discriminant-sizing attrs.)
assert_eq!(hint, attr::ReprAny);
return Univariant(mk_struct(cx, cases[0].tys, false), false)
}
if cases.len() == 2 && hint == attr::ReprAny {
// Nullable pointer optimization
let mut discr = 0;
while discr < 2 {
if cases[1 - discr].is_zerolen(cx) {
@ -205,7 +207,6 @@ fn represent_type_uncached(cx: &mut CrateContext, t: ty::t) -> Repr {
}
// The general case.
let hint = ty::lookup_repr_hint(cx.tcx, def_id);
assert!((cases.len() - 1) as i64 >= 0);
let bounds = IntBounds { ulo: 0, uhi: (cases.len() - 1) as u64,
slo: 0, shi: (cases.len() - 1) as i64 };
@ -307,7 +308,7 @@ fn range_to_inttype(cx: &mut CrateContext, hint: Hint, bounds: &IntBounds) -> In
match hint {
attr::ReprInt(span, ity) => {
if !bounds_usable(cx, ity, bounds) {
cx.sess.span_err(span, "representation hint insufficient for discriminant range")
cx.sess.span_bug(span, "representation hint insufficient for discriminant range")
}
return ity;
}
@ -365,6 +366,7 @@ fn ty_of_inttype(ity: IntType) -> ty::t {
}
}
/**
* Returns the fields of a struct for the given representation.
* All nominal types are LLVM structs, in order to be able to use

54
src/librustc/middle/typeck/check/mod.rs
View File

@ -121,6 +121,7 @@ use syntax::ast;
use syntax::ast_map;
use syntax::ast_util::local_def;
use syntax::ast_util;
use syntax::attr;
use syntax::codemap::Span;
use syntax::codemap;
use syntax::opt_vec::OptVec;
@ -3159,9 +3160,38 @@ pub fn check_enum_variants(ccx: @mut CrateCtxt,
sp: Span,
vs: &[ast::variant],
id: ast::NodeId) {
fn disr_in_range(ccx: @mut CrateCtxt,
ty: attr::IntType,
disr: ty::Disr) -> bool {
fn uint_in_range(ccx: @mut CrateCtxt, ty: ast::uint_ty, disr: ty::Disr) -> bool {
match ty {
ast::ty_u8 => disr as u8 as Disr == disr,
ast::ty_u16 => disr as u16 as Disr == disr,
ast::ty_u32 => disr as u32 as Disr == disr,
ast::ty_u64 => disr as u64 as Disr == disr,
ast::ty_u => uint_in_range(ccx, ccx.tcx.sess.targ_cfg.uint_type, disr)
}
}
fn int_in_range(ccx: @mut CrateCtxt, ty: ast::int_ty, disr: ty::Disr) -> bool {
match ty {
ast::ty_i8 => disr as i8 as Disr == disr,
ast::ty_i16 => disr as i16 as Disr == disr,
ast::ty_i32 => disr as i32 as Disr == disr,
ast::ty_i64 => disr as i64 as Disr == disr,
ast::ty_i => int_in_range(ccx, ccx.tcx.sess.targ_cfg.int_type, disr)
}
}
match ty {
attr::UnsignedInt(ty) => uint_in_range(ccx, ty, disr),
attr::SignedInt(ty) => int_in_range(ccx, ty, disr)
}
}
fn do_check(ccx: @mut CrateCtxt,
vs: &[ast::variant],
id: ast::NodeId)
id: ast::NodeId,
hint: attr::ReprAttr)
-> ~[@ty::VariantInfo] {
let rty = ty::node_id_to_type(ccx.tcx, id);
@ -3203,9 +3233,20 @@ pub fn check_enum_variants(ccx: @mut CrateCtxt,
None => ()
};
// Check for duplicate discriminator values
// Check for duplicate discriminant values
if disr_vals.contains(&current_disr_val) {
ccx.tcx.sess.span_err(v.span, "discriminator value already exists");
ccx.tcx.sess.span_err(v.span, "discriminant value already exists");
}
// Check for unrepresentable discriminant values
match hint {
attr::ReprAny | attr::ReprExtern => (),
attr::ReprInt(sp, ity) => {
if !disr_in_range(ccx, ity, current_disr_val) {
ccx.tcx.sess.span_err(v.span,
"discriminant value outside specified type");
ccx.tcx.sess.span_note(sp, "discriminant type specified here");
}
}
}
disr_vals.push(current_disr_val);
@ -3219,8 +3260,13 @@ pub fn check_enum_variants(ccx: @mut CrateCtxt,
}
let rty = ty::node_id_to_type(ccx.tcx, id);
let hint = ty::lookup_repr_hint(ccx.tcx, ast::DefId { crate: ast::LOCAL_CRATE, node: id });
if hint != attr::ReprAny && vs.len() <= 1 {
ccx.tcx.sess.span_err(sp, format!("unsupported representation for {}variant enum",
if vs.len() == 1 { "uni" } else { "zero-" }))
}
let variants = do_check(ccx, vs, id);
let variants = do_check(ccx, vs, id, hint);
// cache so that ty::enum_variants won't repeat this work
ccx.tcx.enum_var_cache.insert(local_def(id), @variants);

2
src/test/compile-fail/tag-variant-disr-dup.rs
View File

@ -8,7 +8,7 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.
//error-pattern:discriminator value already exists
//error-pattern:discriminant value already exists
// black and white have the same discriminator value ...