From 6046be42ab911cf2eddd41cffaa0467098bb2317 Mon Sep 17 00:00:00 2001 From: mark <markm@cs.wisc.edu> Date: Mon, 14 Jan 2019 15:50:33 -0600 Subject: [PATCH 1/3] fix nested matchers with ? --- src/libsyntax/ext/tt/macro_rules.rs | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/src/libsyntax/ext/tt/macro_rules.rs b/src/libsyntax/ext/tt/macro_rules.rs index 24202ca8fbdc0..9a129e7e8fcd8 100644 --- a/src/libsyntax/ext/tt/macro_rules.rs +++ b/src/libsyntax/ext/tt/macro_rules.rs @@ -435,7 +435,8 @@ fn check_lhs_no_empty_seq(sess: &ParseSess, tts: &[quoted::TokenTree]) -> bool { match *seq_tt { TokenTree::MetaVarDecl(_, _, id) => id.name == "vis", TokenTree::Sequence(_, ref sub_seq) => - sub_seq.op == quoted::KleeneOp::ZeroOrMore, + sub_seq.op == quoted::KleeneOp::ZeroOrMore + || sub_seq.op == quoted::KleeneOp::ZeroOrOne, _ => false, } }) { @@ -543,7 +544,10 @@ impl FirstSets { } // Reverse scan: Sequence comes before `first`. - if subfirst.maybe_empty || seq_rep.op == quoted::KleeneOp::ZeroOrMore { + if subfirst.maybe_empty + || seq_rep.op == quoted::KleeneOp::ZeroOrMore + || seq_rep.op == quoted::KleeneOp::ZeroOrOne + { // If sequence is potentially empty, then // union them (preserving first emptiness). first.add_all(&TokenSet { maybe_empty: true, ..subfirst }); @@ -591,8 +595,10 @@ impl FirstSets { assert!(first.maybe_empty); first.add_all(subfirst); - if subfirst.maybe_empty || - seq_rep.op == quoted::KleeneOp::ZeroOrMore { + if subfirst.maybe_empty + || seq_rep.op == quoted::KleeneOp::ZeroOrMore + || seq_rep.op == quoted::KleeneOp::ZeroOrOne + { // continue scanning for more first // tokens, but also make sure we // restore empty-tracking state From dabe86db44c97698bc6a4ab2f8923a3f65b151f0 Mon Sep 17 00:00:00 2001 From: mark <markm@cs.wisc.edu> Date: Tue, 15 Jan 2019 11:31:49 -0600 Subject: [PATCH 2/3] update/add tests --- src/test/ui/issues/issue-5067.rs | 37 ++++++++++--- src/test/ui/issues/issue-57597.rs | 80 +++++++++++++++++++++++++++ src/test/ui/issues/issue-57597.stderr | 74 +++++++++++++++++++++++++ 3 files changed, 183 insertions(+), 8 deletions(-) create mode 100644 src/test/ui/issues/issue-57597.rs create mode 100644 src/test/ui/issues/issue-57597.stderr diff --git a/src/test/ui/issues/issue-5067.rs b/src/test/ui/issues/issue-5067.rs index 526a68311462e..616fd09907a2b 100644 --- a/src/test/ui/issues/issue-5067.rs +++ b/src/test/ui/issues/issue-5067.rs @@ -1,37 +1,59 @@ #![allow(unused_macros)] +// Tests that repetition matchers cannot match the empty token tree (since that would be +// ambiguous). + +// edition:2018 + macro_rules! foo { ( $()* ) => {}; //~^ ERROR repetition matches empty token tree ( $()+ ) => {}; //~^ ERROR repetition matches empty token tree - + ( $()? ) => {}; + //~^ ERROR repetition matches empty token tree ( $(),* ) => {}; // PASS ( $(),+ ) => {}; // PASS - + // `?` cannot have a separator... ( [$()*] ) => {}; //~^ ERROR repetition matches empty token tree ( [$()+] ) => {}; //~^ ERROR repetition matches empty token tree - + ( [$()?] ) => {}; + //~^ ERROR repetition matches empty token tree ( [$(),*] ) => {}; // PASS ( [$(),+] ) => {}; // PASS - + // `?` cannot have a separator... ( $($()* $(),* $(a)* $(a),* )* ) => {}; //~^ ERROR repetition matches empty token tree ( $($()* $(),* $(a)* $(a),* )+ ) => {}; //~^ ERROR repetition matches empty token tree - + ( $($()* $(),* $(a)* $(a),* )? ) => {}; + //~^ ERROR repetition matches empty token tree + ( $($()? $(),* $(a)? $(a),* )* ) => {}; + //~^ ERROR repetition matches empty token tree + ( $($()? $(),* $(a)? $(a),* )+ ) => {}; + //~^ ERROR repetition matches empty token tree + ( $($()? $(),* $(a)? $(a),* )? ) => {}; + //~^ ERROR repetition matches empty token tree ( $(a $(),* $(a)* $(a),* )* ) => {}; // PASS ( $($(a)+ $(),* $(a)* $(a),* )+ ) => {}; // PASS + ( $($(a)+ $(),* $(a)* $(a),* )? ) => {}; // PASS + + ( $(a $(),* $(a)? $(a),* )* ) => {}; // PASS + ( $($(a)+ $(),* $(a)? $(a),* )+ ) => {}; // PASS + ( $($(a)+ $(),* $(a)? $(a),* )? ) => {}; // PASS ( $(a $()+)* ) => {}; //~^ ERROR repetition matches empty token tree ( $(a $()*)+ ) => {}; //~^ ERROR repetition matches empty token tree + ( $(a $()+)? ) => {}; + //~^ ERROR repetition matches empty token tree + ( $(a $()?)+ ) => {}; + //~^ ERROR repetition matches empty token tree } - // --- Original Issue --- // macro_rules! make_vec { @@ -43,11 +65,10 @@ fn main() { let _ = make_vec![a 1, a 2, a 3]; } - // --- Minified Issue --- // macro_rules! m { - ( $()* ) => {} + ( $()* ) => {}; //~^ ERROR repetition matches empty token tree } diff --git a/src/test/ui/issues/issue-57597.rs b/src/test/ui/issues/issue-57597.rs new file mode 100644 index 0000000000000..ebeb3fe07adb4 --- /dev/null +++ b/src/test/ui/issues/issue-57597.rs @@ -0,0 +1,80 @@ +// Regression test for #57597. +// +// Make sure that nested matchers work correctly rather than causing an infinite loop or crash. + +// edition:2018 + +macro_rules! foo1 { + ($($($i:ident)?)+) => {}; + //~^ ERROR repetition matches empty token tree +} + +macro_rules! foo2 { + ($($($i:ident)?)*) => {}; + //~^ ERROR repetition matches empty token tree +} + +macro_rules! foo3 { + ($($($i:ident)?)?) => {}; + //~^ ERROR repetition matches empty token tree +} + +macro_rules! foo4 { + ($($($($i:ident)?)?)?) => {}; + //~^ ERROR repetition matches empty token tree +} + +macro_rules! foo5 { + ($($($($i:ident)*)?)?) => {}; + //~^ ERROR repetition matches empty token tree +} + +macro_rules! foo6 { + ($($($($i:ident)?)*)?) => {}; + //~^ ERROR repetition matches empty token tree +} + +macro_rules! foo7 { + ($($($($i:ident)?)?)*) => {}; + //~^ ERROR repetition matches empty token tree +} + +macro_rules! foo8 { + ($($($($i:ident)*)*)?) => {}; + //~^ ERROR repetition matches empty token tree +} + +macro_rules! foo9 { + ($($($($i:ident)?)*)*) => {}; + //~^ ERROR repetition matches empty token tree +} + +macro_rules! foo10 { + ($($($($i:ident)?)*)+) => {}; + //~^ ERROR repetition matches empty token tree +} + +macro_rules! foo11 { + ($($($($i:ident)+)?)*) => {}; + //~^ ERROR repetition matches empty token tree +} + +macro_rules! foo12 { + ($($($($i:ident)+)*)?) => {}; + //~^ ERROR repetition matches empty token tree +} + +fn main() { + foo1!(); + foo2!(); + foo3!(); + foo4!(); + foo5!(); + foo6!(); + foo7!(); + foo8!(); + foo9!(); + foo10!(); + foo11!(); + foo12!(); +} diff --git a/src/test/ui/issues/issue-57597.stderr b/src/test/ui/issues/issue-57597.stderr new file mode 100644 index 0000000000000..0a02ac8c499b6 --- /dev/null +++ b/src/test/ui/issues/issue-57597.stderr @@ -0,0 +1,74 @@ +error: repetition matches empty token tree + --> $DIR/issue-57597.rs:8:7 + | +LL | ($($($i:ident)?)+) => {}; + | ^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-57597.rs:13:7 + | +LL | ($($($i:ident)?)*) => {}; + | ^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-57597.rs:18:7 + | +LL | ($($($i:ident)?)?) => {}; + | ^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-57597.rs:23:7 + | +LL | ($($($($i:ident)?)?)?) => {}; + | ^^^^^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-57597.rs:28:7 + | +LL | ($($($($i:ident)*)?)?) => {}; + | ^^^^^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-57597.rs:33:7 + | +LL | ($($($($i:ident)?)*)?) => {}; + | ^^^^^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-57597.rs:38:7 + | +LL | ($($($($i:ident)?)?)*) => {}; + | ^^^^^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-57597.rs:43:7 + | +LL | ($($($($i:ident)*)*)?) => {}; + | ^^^^^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-57597.rs:48:7 + | +LL | ($($($($i:ident)?)*)*) => {}; + | ^^^^^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-57597.rs:53:7 + | +LL | ($($($($i:ident)?)*)+) => {}; + | ^^^^^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-57597.rs:58:7 + | +LL | ($($($($i:ident)+)?)*) => {}; + | ^^^^^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-57597.rs:63:7 + | +LL | ($($($($i:ident)+)*)?) => {}; + | ^^^^^^^^^^^^^^^^^^ + +error: aborting due to 12 previous errors + From aa1ce32b105ff506257019a22684a98b61ab166a Mon Sep 17 00:00:00 2001 From: mark <markm@cs.wisc.edu> Date: Tue, 15 Jan 2019 16:40:10 -0600 Subject: [PATCH 3/3] update test output --- src/test/ui/issues/issue-5067.stderr | 72 +++++++++++++++++++++++----- 1 file changed, 60 insertions(+), 12 deletions(-) diff --git a/src/test/ui/issues/issue-5067.stderr b/src/test/ui/issues/issue-5067.stderr index 433b7c8c04907..7ffc6071407c5 100644 --- a/src/test/ui/issues/issue-5067.stderr +++ b/src/test/ui/issues/issue-5067.stderr @@ -1,62 +1,110 @@ error: repetition matches empty token tree - --> $DIR/issue-5067.rs:4:8 + --> $DIR/issue-5067.rs:9:8 | LL | ( $()* ) => {}; | ^^ error: repetition matches empty token tree - --> $DIR/issue-5067.rs:6:8 + --> $DIR/issue-5067.rs:11:8 | LL | ( $()+ ) => {}; | ^^ error: repetition matches empty token tree - --> $DIR/issue-5067.rs:12:9 + --> $DIR/issue-5067.rs:13:8 + | +LL | ( $()? ) => {}; + | ^^ + +error: repetition matches empty token tree + --> $DIR/issue-5067.rs:18:9 | LL | ( [$()*] ) => {}; | ^^ error: repetition matches empty token tree - --> $DIR/issue-5067.rs:14:9 + --> $DIR/issue-5067.rs:20:9 | LL | ( [$()+] ) => {}; | ^^ error: repetition matches empty token tree - --> $DIR/issue-5067.rs:20:8 + --> $DIR/issue-5067.rs:22:9 + | +LL | ( [$()?] ) => {}; + | ^^ + +error: repetition matches empty token tree + --> $DIR/issue-5067.rs:27:8 | LL | ( $($()* $(),* $(a)* $(a),* )* ) => {}; | ^^^^^^^^^^^^^^^^^^^^^^^^^^ error: repetition matches empty token tree - --> $DIR/issue-5067.rs:22:8 + --> $DIR/issue-5067.rs:29:8 | LL | ( $($()* $(),* $(a)* $(a),* )+ ) => {}; | ^^^^^^^^^^^^^^^^^^^^^^^^^^ error: repetition matches empty token tree - --> $DIR/issue-5067.rs:28:12 + --> $DIR/issue-5067.rs:31:8 + | +LL | ( $($()* $(),* $(a)* $(a),* )? ) => {}; + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-5067.rs:33:8 + | +LL | ( $($()? $(),* $(a)? $(a),* )* ) => {}; + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-5067.rs:35:8 + | +LL | ( $($()? $(),* $(a)? $(a),* )+ ) => {}; + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-5067.rs:37:8 + | +LL | ( $($()? $(),* $(a)? $(a),* )? ) => {}; + | ^^^^^^^^^^^^^^^^^^^^^^^^^^ + +error: repetition matches empty token tree + --> $DIR/issue-5067.rs:47:12 | LL | ( $(a $()+)* ) => {}; | ^^ error: repetition matches empty token tree - --> $DIR/issue-5067.rs:30:12 + --> $DIR/issue-5067.rs:49:12 | LL | ( $(a $()*)+ ) => {}; | ^^ error: repetition matches empty token tree - --> $DIR/issue-5067.rs:38:18 + --> $DIR/issue-5067.rs:51:12 + | +LL | ( $(a $()+)? ) => {}; + | ^^ + +error: repetition matches empty token tree + --> $DIR/issue-5067.rs:53:12 + | +LL | ( $(a $()?)+ ) => {}; + | ^^ + +error: repetition matches empty token tree + --> $DIR/issue-5067.rs:60:18 | LL | (a $e1:expr $($(, a $e2:expr)*)*) => ([$e1 $($(, $e2)*)*]); | ^^^^^^^^^^^^^^^^^^ error: repetition matches empty token tree - --> $DIR/issue-5067.rs:50:8 + --> $DIR/issue-5067.rs:71:8 | -LL | ( $()* ) => {} +LL | ( $()* ) => {}; | ^^ -error: aborting due to 10 previous errors +error: aborting due to 18 previous errors