rustc_codegen_llvm: don't generate any type debuginfo for -Cdebuginfo=1.

src/librustc_codegen_llvm/debuginfo/create_scope_map.rs

@@ -1,11 +1,13 @@
 use super::metadata::{file_metadata, UNKNOWN_COLUMN_NUMBER, UNKNOWN_LINE_NUMBER};
 use super::utils::DIB;
 use rustc_codegen_ssa::mir::debuginfo::{DebugScope, FunctionDebugContext};
+use rustc_codegen_ssa::traits::*;
 
 use crate::common::CodegenCx;
 use crate::llvm;
 use crate::llvm::debuginfo::{DIScope, DISubprogram};
 use rustc::mir::{Body, SourceScope};
+use rustc_session::config::DebugInfo;
 
 use rustc_index::bit_set::BitSet;
 use rustc_index::vec::Idx;
@@ -19,10 +21,17 @@ pub fn compute_mir_scopes(
 ) {
     // Find all the scopes with variables defined in them.
     let mut has_variables = BitSet::new_empty(mir.source_scopes.len());
-    // FIXME(eddyb) take into account that arguments always have debuginfo,
-    // irrespective of their name (assuming full debuginfo is enabled).
-    for var_debug_info in &mir.var_debug_info {
-        has_variables.insert(var_debug_info.source_info.scope);
+
+    // Only consider variables when they're going to be emitted.
+    // FIXME(eddyb) don't even allocate `has_variables` otherwise.
+    if cx.sess().opts.debuginfo == DebugInfo::Full {
+        // FIXME(eddyb) take into account that arguments always have debuginfo,
+        // irrespective of their name (assuming full debuginfo is enabled).
+        // NOTE(eddyb) actually, on second thought, those are always in the
+        // function scope, which always exists.
+        for var_debug_info in &mir.var_debug_info {
+            has_variables.insert(var_debug_info.source_info.scope);
+        }
     }
 
     // Instantiate all scopes.

src/librustc_codegen_llvm/debuginfo/metadata.rs

@@ -2299,6 +2299,11 @@ pub fn create_global_var_metadata(cx: &CodegenCx<'ll, '_>, def_id: DefId, global
         return;
     }
 
+    // Only create type information if full debuginfo is enabled
+    if cx.sess().opts.debuginfo != DebugInfo::Full {
+        return;
+    }
+
     let tcx = cx.tcx;
     let attrs = tcx.codegen_fn_attrs(def_id);
 
@@ -2358,6 +2363,11 @@ pub fn create_vtable_metadata(cx: &CodegenCx<'ll, 'tcx>, ty: Ty<'tcx>, vtable: &
         return;
     }
 
+    // Only create type information if full debuginfo is enabled
+    if cx.sess().opts.debuginfo != DebugInfo::Full {
+        return;
+    }
+
     let type_metadata = type_metadata(cx, ty, rustc_span::DUMMY_SP);
 
     unsafe {

src/librustc_codegen_llvm/debuginfo/mod.rs

@@ -475,7 +475,12 @@ impl DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
                     // so avoid methods on other types (e.g., `<*mut T>::null`).
                     match impl_self_ty.kind {
                         ty::Adt(def, ..) if !def.is_box() => {
-                            Some(type_metadata(cx, impl_self_ty, rustc_span::DUMMY_SP))
+                            // Again, only create type information if full debuginfo is enabled
+                            if cx.sess().opts.debuginfo == DebugInfo::Full {
+                                Some(type_metadata(cx, impl_self_ty, rustc_span::DUMMY_SP))
+                            } else {
+                                Some(namespace::item_namespace(cx, def.did))
+                            }
                         }
                         _ => None,
                     }

src/librustc_llvm/build.rs

@@ -151,6 +151,7 @@ fn main() {
 
     if env::var_os("LLVM_NDEBUG").is_some() {
         cfg.define("NDEBUG", None);
+        cfg.debug(false);
     }
 
     build_helper::rerun_if_changed_anything_in_dir(Path::new("../rustllvm"));