Add "trace-macros" as a compiler flag

Fixes #22619

2 files changed, 4 insertions, 4 deletions

diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs
index 9994fad3e31..9c2837d71ff 100644
--- a/src/libsyntax/ext/base.rs
+++ b/src/libsyntax/ext/base.rs
@@ -554,7 +554,6 @@ pub struct ExtCtxt<'a> {
     pub use_std: bool,
 
     pub mod_path: Vec<ast::Ident> ,
-    pub trace_mac: bool,
     pub exported_macros: Vec<ast::MacroDef>,
 
     pub syntax_env: SyntaxEnv,
@@ -572,7 +571,6 @@ impl<'a> ExtCtxt<'a> {
             mod_path: Vec::new(),
             ecfg: ecfg,
             use_std: true,
-            trace_mac: false,
             exported_macros: Vec::new(),
             syntax_env: env,
             recursion_count: 0,
@@ -732,10 +730,10 @@ impl<'a> ExtCtxt<'a> {
         self.parse_sess.span_diagnostic.handler().bug(msg);
     }
     pub fn trace_macros(&self) -> bool {
-        self.trace_mac
+        self.ecfg.trace_mac
     }
     pub fn set_trace_macros(&mut self, x: bool) {
-        self.trace_mac = x
+        self.ecfg.trace_mac = x
     }
     pub fn ident_of(&self, st: &str) -> ast::Ident {
         str_to_ident(st)
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs
index b65798b8a49..c8ff08eeb94 100644
--- a/src/libsyntax/ext/expand.rs
+++ b/src/libsyntax/ext/expand.rs
@@ -1406,6 +1406,7 @@ pub struct ExpansionConfig<'feat> {
     pub crate_name: String,
     pub features: Option<&'feat Features>,
     pub recursion_limit: usize,
+    pub trace_mac: bool,
 }
 
 macro_rules! feature_tests {
@@ -1427,6 +1428,7 @@ impl<'feat> ExpansionConfig<'feat> {
             crate_name: crate_name,
             features: None,
             recursion_limit: 64,
+            trace_mac: false,
         }
     }