diff --git a/src/parse/macros/cfg_if.rs b/src/parse/macros/cfg_if.rs
index 5fc988e4319..638c3c1267b 100644
--- a/src/parse/macros/cfg_if.rs
+++ b/src/parse/macros/cfg_if.rs
@@ -2,7 +2,7 @@ use std::panic::{catch_unwind, AssertUnwindSafe};
use rustc_ast::ast;
use rustc_ast::token::{Delimiter, TokenKind};
-use rustc_parse::parser::ForceCollect;
+use rustc_parse::parser::{ForceCollect, Parser};
use rustc_span::symbol::kw;
use crate::parse::macros::build_stream_parser;
@@ -31,32 +31,7 @@ fn parse_cfg_if_inner<'a>(
while parser.token.kind != TokenKind::Eof {
if process_if_cfg {
- if !parser.eat_keyword(kw::If) {
- return Err("Expected `if`");
- }
-
- if !matches!(parser.token.kind, TokenKind::Pound) {
- return Err("Failed to parse attributes");
- }
-
- // Inner attributes are not actually syntactically permitted here, but we don't
- // care about inner vs outer attributes in this position. Our purpose with this
- // special case parsing of cfg_if macros is to ensure we can correctly resolve
- // imported modules that may have a custom `path` defined.
- //
- // As such, we just need to advance the parser past the attribute and up to
- // to the opening brace.
- // See also https://github.com/rust-lang/rust/pull/79433
- parser
- .parse_attribute(rustc_parse::parser::attr::InnerAttrPolicy::Permitted)
- .map_err(|e| {
- e.cancel();
- "Failed to parse attributes"
- })?;
- }
-
- if !parser.eat(&TokenKind::OpenDelim(Delimiter::Brace)) {
- return Err("Expected an opening brace");
+ eat_if(&mut parser)?;
}
while parser.token != TokenKind::CloseDelim(Delimiter::Brace)
@@ -64,7 +39,17 @@ fn parse_cfg_if_inner<'a>(
{
let item = match parser.parse_item(ForceCollect::No) {
Ok(Some(item_ptr)) => item_ptr.into_inner(),
- Ok(None) => continue,
+ Ok(None) => {
+ if matches!(parser.token.kind, TokenKind::Ident(symbol, ..) if symbol == kw::If)
+ {
+ // eat a nested if
+ eat_if(&mut parser)?;
+ } else {
+ // Not sure what token we're on. To prevent infinite loops bump the parser
+ parser.bump();
+ }
+ continue;
+ }
Err(err) => {
err.cancel();
parser.psess.dcx.reset_err_count();
@@ -82,12 +67,15 @@ fn parse_cfg_if_inner<'a>(
return Err("Expected a closing brace");
}
- if parser.eat(&TokenKind::Eof) {
- break;
+ if matches!(parser.token.kind, TokenKind::Ident(symbol, ..) if symbol == kw::Else) {
+ // there might be an `else` after the `if`
+ parser.eat_keyword(kw::Else);
+ // there might be an opening brace after the `else`, but it might also be an `else if`
+ parser.eat(&TokenKind::OpenDelim(Delimiter::Brace));
}
- if !parser.eat_keyword(kw::Else) {
- return Err("Expected `else`");
+ if parser.eat(&TokenKind::Eof) {
+ break;
}
process_if_cfg = parser.token.is_keyword(kw::If);
@@ -95,3 +83,33 @@ fn parse_cfg_if_inner<'a>(
Ok(items)
}
+
+fn eat_if(parser: &mut Parser<'_>) -> Result<(), &'static str> {
+ if !parser.eat_keyword(kw::If) {
+ return Err("Expected `if`");
+ }
+
+ if !matches!(parser.token.kind, TokenKind::Pound) {
+ return Err("Failed to parse attributes");
+ }
+
+ // Inner attributes are not actually syntactically permitted here, but we don't
+ // care about inner vs outer attributes in this position. Our purpose with this
+ // special case parsing of cfg_if macros is to ensure we can correctly resolve
+ // imported modules that may have a custom `path` defined.
+ //
+ // As such, we just need to advance the parser past the attribute and up to
+ // to the opening brace.
+ // See also https://github.com/rust-lang/rust/pull/79433
+ parser
+ .parse_attribute(rustc_parse::parser::attr::InnerAttrPolicy::Permitted)
+ .map_err(|e| {
+ e.cancel();
+ "Failed to parse attributes"
+ })?;
+
+ if !parser.eat(&TokenKind::OpenDelim(Delimiter::Brace)) {
+ return Err("Expected an opening brace");
+ }
+ Ok(())
+}
diff --git a/tests/source/issue-4442/a.rs b/tests/source/issue-4442/a.rs
new file mode 100644
index 00000000000..4278f0f85b8
--- /dev/null
+++ b/tests/source/issue-4442/a.rs
@@ -0,0 +1,2 @@
+fn a ()
+{println!("mod a")}
diff --git a/tests/source/issue-4442/b.rs b/tests/source/issue-4442/b.rs
new file mode 100644
index 00000000000..da69971945b
--- /dev/null
+++ b/tests/source/issue-4442/b.rs
@@ -0,0 +1,2 @@
+fn b ()
+{println!("mod b")}
diff --git a/tests/source/issue-4442/c.rs b/tests/source/issue-4442/c.rs
new file mode 100644
index 00000000000..43fadb4146d
--- /dev/null
+++ b/tests/source/issue-4442/c.rs
@@ -0,0 +1,2 @@
+fn c ()
+{println!("mod c")}
diff --git a/tests/source/issue-4442/d.rs b/tests/source/issue-4442/d.rs
new file mode 100644
index 00000000000..99a9598f325
--- /dev/null
+++ b/tests/source/issue-4442/d.rs
@@ -0,0 +1,2 @@
+fn d ()
+{println!("mod d")}
diff --git a/tests/source/issue-4442/e.rs b/tests/source/issue-4442/e.rs
new file mode 100644
index 00000000000..dc28c824946
--- /dev/null
+++ b/tests/source/issue-4442/e.rs
@@ -0,0 +1,2 @@
+fn e ()
+{println!("mod e")}
diff --git a/tests/source/issue-4442/lib.rs b/tests/source/issue-4442/lib.rs
new file mode 100644
index 00000000000..4eddbfa28fa
--- /dev/null
+++ b/tests/source/issue-4442/lib.rs
@@ -0,0 +1,26 @@
+// main.rs
+cfg_if::cfg_if! {
+ if #[cfg(not(feature = "client"))] {
+ mod a;
+ if #[cfg(feature = "server")] {
+ if #[cfg(not(feature = "client"))] {
+ if #[cfg(feature = "server")] {
+ if #[cfg(not(feature = "client"))] {
+ mod b;
+ } else {
+ mod c;
+ }
+ if #[cfg(feature = "server")] {
+ if #[cfg(not(feature = "client"))] {
+ if #[cfg(feature = "server")] {
+ mod d;
+ } else {
+ mod e;
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+}
diff --git a/tests/source/issue_5413.rs b/tests/source/issue_5413.rs
new file mode 100644
index 00000000000..c4952f69cba
--- /dev/null
+++ b/tests/source/issue_5413.rs
@@ -0,0 +1,16 @@
+cfg_if! {
+ if
+}
+
+cfg_if! {
+ if #[a] { } else if
+}
+
+cfg_if! {
+ if #[a] { if }
+}
+
+fn main(
+ ) {
+println!("hello world!");
+ }
diff --git a/tests/target/issue-4442/a.rs b/tests/target/issue-4442/a.rs
new file mode 100644
index 00000000000..6ee01582a2c
--- /dev/null
+++ b/tests/target/issue-4442/a.rs
@@ -0,0 +1,3 @@
+fn a() {
+ println!("mod a")
+}
diff --git a/tests/target/issue-4442/b.rs b/tests/target/issue-4442/b.rs
new file mode 100644
index 00000000000..c1a0a54d143
--- /dev/null
+++ b/tests/target/issue-4442/b.rs
@@ -0,0 +1,3 @@
+fn b() {
+ println!("mod b")
+}
diff --git a/tests/target/issue-4442/c.rs b/tests/target/issue-4442/c.rs
new file mode 100644
index 00000000000..1e4661c5033
--- /dev/null
+++ b/tests/target/issue-4442/c.rs
@@ -0,0 +1,3 @@
+fn c() {
+ println!("mod c")
+}
diff --git a/tests/target/issue-4442/d.rs b/tests/target/issue-4442/d.rs
new file mode 100644
index 00000000000..3679b181da8
--- /dev/null
+++ b/tests/target/issue-4442/d.rs
@@ -0,0 +1,3 @@
+fn d() {
+ println!("mod d")
+}
diff --git a/tests/target/issue-4442/e.rs b/tests/target/issue-4442/e.rs
new file mode 100644
index 00000000000..5a21024b9ac
--- /dev/null
+++ b/tests/target/issue-4442/e.rs
@@ -0,0 +1,3 @@
+fn e() {
+ println!("mod e")
+}
diff --git a/tests/target/issue-4442/lib.rs b/tests/target/issue-4442/lib.rs
new file mode 100644
index 00000000000..4eddbfa28fa
--- /dev/null
+++ b/tests/target/issue-4442/lib.rs
@@ -0,0 +1,26 @@
+// main.rs
+cfg_if::cfg_if! {
+ if #[cfg(not(feature = "client"))] {
+ mod a;
+ if #[cfg(feature = "server")] {
+ if #[cfg(not(feature = "client"))] {
+ if #[cfg(feature = "server")] {
+ if #[cfg(not(feature = "client"))] {
+ mod b;
+ } else {
+ mod c;
+ }
+ if #[cfg(feature = "server")] {
+ if #[cfg(not(feature = "client"))] {
+ if #[cfg(feature = "server")] {
+ mod d;
+ } else {
+ mod e;
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+}
diff --git a/tests/target/issue_5413.rs b/tests/target/issue_5413.rs
new file mode 100644
index 00000000000..67f7e06d6a4
--- /dev/null
+++ b/tests/target/issue_5413.rs
@@ -0,0 +1,15 @@
+cfg_if! {
+ if
+}
+
+cfg_if! {
+ if #[a] { } else if
+}
+
+cfg_if! {
+ if #[a] { if }
+}
+
+fn main() {
+ println!("hello world!");
+}
diff --git a/tests/target/issue_5428.rs b/tests/target/issue_5428.rs
new file mode 100644
index 00000000000..727d8e4c20f
--- /dev/null
+++ b/tests/target/issue_5428.rs
@@ -0,0 +1,6 @@
+// cfg-if: version 1.0.0
+cfg_if::cfg_if! {
+ if #[cfg(windows)] {
+ compile_error!{"..."};
+ }
+}
diff --git a/tests/target/issue_6215.rs b/tests/target/issue_6215.rs
new file mode 100644
index 00000000000..abfce77b4f4
--- /dev/null
+++ b/tests/target/issue_6215.rs
@@ -0,0 +1,9 @@
+cfg_if!(
+ if #[cfg(feature = "xxxx")] {
+ if #[cfg(feature = "yyyy")] {
+ pub const C1: u8 = 1;
+ } else {
+ pub const C2: u8 = 2;
+ }
+ }
+);