auto merge of #17963 : sfackler/rust/cfg-error, r=alexcrichton

All deprecation warnings have been converted to errors. This includes
the warning for multiple cfgs on one item. We'll leave that as an error
for some period of time to ensure that all uses are updated before the
behavior changes from "or" to "and".

Author: bors

src/doc/guide-ffi.md

@@ -475,7 +475,7 @@ conventions. Rust provides a way to tell the compiler which convention to use:
 ~~~~
 extern crate libc;
 
-#[cfg(target_os = "win32", target_arch = "x86")]
+#[cfg(all(target_os = "win32", target_arch = "x86"))]
 #[link(name = "kernel32")]
 #[allow(non_snake_case)]
 extern "stdcall" {

src/doc/guide-unsafe.md

@@ -313,17 +313,15 @@ literal string (i.e `""`)
 ```
 #![feature(asm)]
 
-#[cfg(target_arch = "x86")]
-#[cfg(target_arch = "x86_64")]
+#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
 fn foo() {
     unsafe {
         asm!("NOP");
     }
 }
 
 // other platforms
-#[cfg(not(target_arch = "x86"),
-      not(target_arch = "x86_64"))]
+#[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]
 fn foo() { /* ... */ }
 
 fn main() {
@@ -340,7 +338,7 @@ but you must add the right number of `:` if you skip them:
 
 ```
 # #![feature(asm)]
-# #[cfg(target_arch = "x86")] #[cfg(target_arch = "x86_64")]
+# #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
 # fn main() { unsafe {
 asm!("xor %eax, %eax"
     :
@@ -354,7 +352,7 @@ Whitespace also doesn't matter:
 
 ```
 # #![feature(asm)]
-# #[cfg(target_arch = "x86")] #[cfg(target_arch = "x86_64")]
+# #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
 # fn main() { unsafe {
 asm!("xor %eax, %eax" ::: "eax");
 # } }
@@ -368,7 +366,7 @@ expressions must be mutable lvalues:
 
 ```
 # #![feature(asm)]
-# #[cfg(target_arch = "x86")] #[cfg(target_arch = "x86_64")]
+# #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
 fn add(a: int, b: int) -> int {
     let mut c = 0;
     unsafe {
@@ -379,7 +377,7 @@ fn add(a: int, b: int) -> int {
     }
     c
 }
-# #[cfg(not(target_arch = "x86"), not(target_arch = "x86_64"))]
+# #[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]
 # fn add(a: int, b: int) -> int { a + b }
 
 fn main() {
@@ -396,7 +394,7 @@ stay valid.
 
 ```
 # #![feature(asm)]
-# #[cfg(target_arch = "x86")] #[cfg(target_arch = "x86_64")]
+# #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
 # fn main() { unsafe {
 // Put the value 0x200 in eax
 asm!("mov $$0x200, %eax" : /* no outputs */ : /* no inputs */ : "eax");

src/doc/reference.md

@@ -2049,26 +2049,28 @@ fn macos_only() {
 }
 
 // This function is only included when either foo or bar is defined
-#[cfg(foo)]
-#[cfg(bar)]
+#[cfg(any(foo, bar))]
 fn needs_foo_or_bar() {
   // ...
 }
 
 // This function is only included when compiling for a unixish OS with a 32-bit
 // architecture
-#[cfg(unix, target_word_size = "32")]
+#[cfg(all(unix, target_word_size = "32"))]
 fn on_32bit_unix() {
   // ...
 }
+
+// This function is only included when foo is not defined
+#[cfg(not(foo))]
+fn needs_not_foo() {
+  // ...
+}
 ```
 
 This illustrates some conditional compilation can be achieved using the
-`#[cfg(...)]` attribute. Note that `#[cfg(foo, bar)]` is a condition that needs
-both `foo` and `bar` to be defined while `#[cfg(foo)] #[cfg(bar)]` only needs
-one of `foo` and `bar` to be defined (this resembles in the disjunctive normal
-form). Additionally, one can reverse a condition by enclosing it in a
-`not(...)`, like e. g. `#[cfg(not(target_os = "win32"))]`.
+`#[cfg(...)]` attribute. `any`, `all` and `not` can be used to assemble
+arbitrarily complex configurations through nesting.
 
 The following configurations must be defined by the implementation:
 

src/libsyntax/attr.rs

@@ -316,11 +316,10 @@ pub fn cfg_matches(diagnostic: &SpanHandler, cfgs: &[P<MetaItem>], cfg: &ast::Me
             mis.iter().all(|mi| cfg_matches(diagnostic, cfgs, &**mi)),
         ast::MetaList(ref pred, ref mis) if pred.get() == "not" => {
             if mis.len() != 1 {
-                diagnostic.span_warn(cfg.span, "the use of multiple cfgs in the same `not` \
-                                                statement is deprecated. Change `not(a, b)` to \
-                                                `not(all(a, b))`.");
+                diagnostic.span_err(cfg.span, "expected 1 cfg-pattern");
+                return false;
             }
-            !mis.iter().all(|mi| cfg_matches(diagnostic, cfgs, &**mi))
+            !cfg_matches(diagnostic, cfgs, &*mis[0])
         }
         ast::MetaList(ref pred, _) => {
             diagnostic.span_err(cfg.span, format!("invalid predicate `{}`", pred).as_slice());
@@ -330,56 +329,6 @@ pub fn cfg_matches(diagnostic: &SpanHandler, cfgs: &[P<MetaItem>], cfg: &ast::Me
     }
 }
 
-/// Tests if any `cfg(...)` meta items in `metas` match `cfg`. e.g.
-///
-/// test_cfg(`[foo="a", bar]`, `[cfg(foo), cfg(bar)]`) == true
-/// test_cfg(`[foo="a", bar]`, `[cfg(not(bar))]`) == false
-/// test_cfg(`[foo="a", bar]`, `[cfg(bar, foo="a")]`) == true
-/// test_cfg(`[foo="a", bar]`, `[cfg(bar, foo="b")]`) == false
-pub fn test_cfg<'a, AM: AttrMetaMethods, It: Iterator<&'a AM>>
-    (cfg: &[P<MetaItem>], mut metas: It) -> bool {
-    // having no #[cfg(...)] attributes counts as matching.
-    let mut no_cfgs = true;
-
-    // this would be much nicer as a chain of iterator adaptors, but
-    // this doesn't work.
-    let some_cfg_matches = metas.fold(false, |matches, mi| {
-        debug!("testing name: {}", mi.name());
-        let this_matches = if mi.check_name("cfg") { // it is a #[cfg()] attribute
-            debug!("is cfg");
-            no_cfgs = false;
-             // only #[cfg(...)] ones are understood.
-            match mi.meta_item_list() {
-                Some(cfg_meta) => {
-                    debug!("is cfg(...)");
-                    cfg_meta.iter().all(|cfg_mi| {
-                        debug!("cfg({}[...])", cfg_mi.name());
-                        match cfg_mi.node {
-                            ast::MetaList(ref s, ref not_cfgs)
-                            if s.equiv(&("not")) => {
-                                debug!("not!");
-                                // inside #[cfg(not(...))], so these need to all
-                                // not match.
-                                !not_cfgs.iter().all(|mi| {
-                                    debug!("cfg(not({}[...]))", mi.name());
-                                    contains(cfg, &**mi)
-                                })
-                            }
-                            _ => contains(cfg, &**cfg_mi)
-                        }
-                    })
-                }
-                None => false
-            }
-        } else {
-            false
-        };
-        matches || this_matches
-    });
-    debug!("test_cfg (no_cfgs={}, some_cfg_matches={})", no_cfgs, some_cfg_matches);
-    no_cfgs || some_cfg_matches
-}
-
 /// Represents the #[deprecated="foo"] and friends attributes.
 #[deriving(Encodable,Decodable,Clone,Show)]
 pub struct Stability {

src/libsyntax/config.rs

@@ -259,20 +259,20 @@ fn in_cfg(diagnostic: &SpanHandler, cfg: &[P<ast::MetaItem>], attrs: &[ast::Attr
         };
 
         if mis.len() != 1 {
-            diagnostic.span_warn(attr.span, "The use of multiple cfgs in the top level of \
-                                             `#[cfg(..)]` is deprecated. Change `#[cfg(a, b)]` to \
-                                             `#[cfg(all(a, b))]`.");
+            diagnostic.span_err(attr.span, "expected 1 cfg-pattern");
+            return false;
         }
 
         if seen_cfg {
-            diagnostic.span_warn(attr.span, "The semantics of multiple `#[cfg(..)]` attributes on \
-                                             same item are changing from the union of the cfgs to \
-                                             the intersection of the cfgs. Change `#[cfg(a)] \
-                                             #[cfg(b)]` to `#[cfg(any(a, b))]`.");
+            diagnostic.span_err(attr.span, "The semantics of multiple `#[cfg(..)]` attributes on \
+                                            same item are changing from the union of the cfgs to \
+                                            the intersection of the cfgs. Change `#[cfg(a)] \
+                                            #[cfg(b)]` to `#[cfg(any(a, b))]`.");
+            return false;
         }
 
         seen_cfg = true;
-        in_cfg |= mis.iter().all(|mi| attr::cfg_matches(diagnostic, cfg, &**mi));
+        in_cfg |= attr::cfg_matches(diagnostic, cfg, &*mis[0]);
     }
     in_cfg | !seen_cfg
 }

src/libsyntax/ext/cfg.rs

@@ -8,11 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-/**
-The compiler code necessary to support the cfg! extension, which
-expands to a literal `true` or `false` based on whether the given cfgs
-match the current compilation environment.
-*/
+/// The compiler code necessary to support the cfg! extension, which expands to
+/// a literal `true` or `false` based on whether the given cfg matches the
+/// current compilation environment.
 
 use ast;
 use codemap::Span;
@@ -24,28 +22,18 @@ use attr::*;
 use parse::attr::ParserAttr;
 use parse::token;
 
-
 pub fn expand_cfg<'cx>(cx: &mut ExtCtxt,
                        sp: Span,
                        tts: &[ast::TokenTree])
                        -> Box<base::MacResult+'static> {
     let mut p = cx.new_parser_from_tts(tts);
-    let mut cfgs = Vec::new();
-    // parse `cfg!(meta_item, meta_item(x,y), meta_item="foo", ...)`
-    while p.token != token::EOF {
-        cfgs.push(p.parse_meta_item());
-        if p.eat(&token::EOF) { break } // trailing comma is optional,.
-        p.expect(&token::COMMA);
-    }
+    let cfg = p.parse_meta_item();
 
-    if cfgs.len() != 1 {
-        cx.span_warn(sp, "The use of multiple cfgs at the top level of `cfg!` \
-                          is deprecated. Change `cfg!(a, b)` to \
-                          `cfg!(all(a, b))`.");
+    if !p.eat(&token::EOF) {
+        cx.span_err(sp, "expected 1 cfg-pattern");
+        return DummyResult::expr(sp);
     }
 
-    let matches_cfg = cfgs.iter().all(|cfg| attr::cfg_matches(&cx.parse_sess.span_diagnostic,
-                                                              cx.cfg.as_slice(), &**cfg));
-
+    let matches_cfg = attr::cfg_matches(&cx.parse_sess.span_diagnostic, cx.cfg.as_slice(), &*cfg);
     MacExpr::new(cx.expr_bool(sp, matches_cfg))
 }

src/libsyntax/test.rs

@@ -126,7 +126,7 @@ impl<'a> fold::Folder for TestHarnessGenerator<'a> {
                         span: i.span,
                         path: self.cx.path.clone(),
                         bench: is_bench_fn(&self.cx, &*i),
-                        ignore: is_ignored(&self.cx, &*i),
+                        ignore: is_ignored(&*i),
                         should_fail: should_fail(&*i)
                     };
                     self.cx.testfns.push(test);
@@ -343,22 +343,8 @@ fn is_bench_fn(cx: &TestCtxt, i: &ast::Item) -> bool {
     return has_bench_attr && has_test_signature(i);
 }
 
-fn is_ignored(cx: &TestCtxt, i: &ast::Item) -> bool {
-    i.attrs.iter().any(|attr| {
-        // check ignore(cfg(foo, bar))
-        attr.check_name("ignore") && match attr.meta_item_list() {
-            Some(ref cfgs) => {
-                if cfgs.iter().any(|cfg| cfg.check_name("cfg")) {
-                    cx.span_diagnostic.span_warn(attr.span,
-                            "The use of cfg filters in #[ignore] is \
-                             deprecated. Use #[cfg_attr(<cfg pattern>, \
-                             ignore)] instead.");
-                }
-                attr::test_cfg(cx.config.as_slice(), cfgs.iter())
-            }
-            None => true
-        }
-    })
+fn is_ignored(i: &ast::Item) -> bool {
+    i.attrs.iter().any(|attr| attr.check_name("ignore"))
 }
 
 fn should_fail(i: &ast::Item) -> bool {

src/test/auxiliary/extern_calling_convention.rs

@@ -26,8 +26,7 @@ pub extern "win64" fn foo(a: int, b: int, c: int, d: int) {
 }
 
 #[inline(never)]
-#[cfg(target_arch = "x86")]
-#[cfg(target_arch = "arm")]
+#[cfg(any(target_arch = "x86", target_arch = "arm"))]
 pub extern fn foo(a: int, b: int, c: int, d: int) {
     assert!(a == 1);
     assert!(b == 2);

src/test/run-make/test-harness/test-ignore-cfg.rs

@@ -9,11 +9,11 @@
 // except according to those terms.
 
 #[test]
-#[ignore(cfg(ignorecfg))]
+#[cfg_attr(ignorecfg, ignore)]
 fn shouldignore() {
 }
 
 #[test]
-#[ignore(cfg(noignorecfg))]
+#[cfg_attr(noignorecfg, ignore)]
 fn shouldnotignore() {
 }

src/test/run-pass/asm-in-out-operand.rs

@@ -10,8 +10,7 @@
 
 #![feature(asm)]
 
-#[cfg(target_arch = "x86")]
-#[cfg(target_arch = "x86_64")]
+#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
 unsafe fn next_power_of_2(n: u32) -> u32 {
     let mut tmp = n;
     asm!("dec $0" : "+rm"(tmp) :: "cc");
@@ -28,8 +27,7 @@ unsafe fn next_power_of_2(n: u32) -> u32 {
     return tmp;
 }
 
-#[cfg(target_arch = "x86")]
-#[cfg(target_arch = "x86_64")]
+#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
 pub fn main() {
     unsafe {
         assert_eq!(64, next_power_of_2(37));
@@ -62,5 +60,5 @@ pub fn main() {
     assert_eq!(x, 60);
 }
 
-#[cfg(not(target_arch = "x86"), not(target_arch = "x86_64"))]
+#[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]
 pub fn main() {}