Handle special names by using GetIRBaseName()

carbon-language · Feb 28, 2025 · 29e1548 · 29e1548
1 parent 3ec0ec8
commit 29e1548
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Showing 2 changed files with 54 additions and 3 deletions.
diff --git a/toolchain/check/import_cpp.cpp b/toolchain/check/import_cpp.cpp
@@ -156,14 +156,13 @@ static auto ClangLookup(Context& context, SemIR::LocId loc_id,
   CARBON_CHECK(ast);
   clang::Sema& sema = ast->getSema();
 
-  auto name = context.names().GetAsStringIfIdentifier(name_id);
-  CARBON_CHECK(name);
+  llvm::StringRef name = context.names().GetIRBaseName(name_id);
 
   clang::LookupResult lookup(
       sema,
       clang::DeclarationNameInfo(
           clang::DeclarationName(
-              sema.getPreprocessor().getIdentifierInfo(*name)),
+              sema.getPreprocessor().getIdentifierInfo(name)),
           clang::SourceLocation()),
       clang::Sema::LookupNameKind::LookupOrdinaryName);
 

diff --git a/toolchain/check/testdata/interop/cpp/no_prelude/function_decl.carbon b/toolchain/check/testdata/interop/cpp/no_prelude/function_decl.carbon
@@ -22,6 +22,20 @@ fn MyF() {
   Cpp.foo();
 }
 
+// --- function_special_name_decl.h
+
+void base();
+
+// --- import_function_special_name_decl.carbon
+
+library "[[@TEST_NAME]]";
+
+import Cpp library "function_special_name_decl.h";
+
+fn MyF() {
+  Cpp.base();
+}
+
 // --- overloaded_function_decl.h
 
 void foo();
@@ -194,6 +208,44 @@ fn F() {
 // CHECK:STDOUT:
 // CHECK:STDOUT: fn @foo[]();
 // CHECK:STDOUT:
+// CHECK:STDOUT: --- import_function_special_name_decl.carbon
+// CHECK:STDOUT:
+// CHECK:STDOUT: constants {
+// CHECK:STDOUT:   %MyF.type: type = fn_type @MyF [concrete]
+// CHECK:STDOUT:   %empty_tuple.type: type = tuple_type () [concrete]
+// CHECK:STDOUT:   %MyF: %MyF.type = struct_value () [concrete]
+// CHECK:STDOUT:   %base.type: type = fn_type @base [concrete]
+// CHECK:STDOUT:   %base: %base.type = struct_value () [concrete]
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: imports {
+// CHECK:STDOUT:   %Cpp: <namespace> = namespace file.%Cpp.import_cpp, [concrete] {
+// CHECK:STDOUT:     .base = @MyF.%base.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: file {
+// CHECK:STDOUT:   package: <namespace> = namespace [concrete] {
+// CHECK:STDOUT:     .Cpp = imports.%Cpp
+// CHECK:STDOUT:     .MyF = %MyF.decl
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %Cpp.import_cpp = import_cpp {
+// CHECK:STDOUT:     import Cpp "function_special_name_decl.h"
+// CHECK:STDOUT:   }
+// CHECK:STDOUT:   %MyF.decl: %MyF.type = fn_decl @MyF [concrete = constants.%MyF] {} {}
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: fn @MyF() {
+// CHECK:STDOUT: !entry:
+// CHECK:STDOUT:   %Cpp.ref: <namespace> = name_ref Cpp, imports.%Cpp [concrete = imports.%Cpp]
+// CHECK:STDOUT:   %base.decl: %base.type = fn_decl @base [concrete = constants.%base] {} {}
+// CHECK:STDOUT:   %base.ref: %base.type = name_ref base, %base.decl [concrete = constants.%base]
+// CHECK:STDOUT:   %base.call: init %empty_tuple.type = call %base.ref()
+// CHECK:STDOUT:   return
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: fn @base[]();
+// CHECK:STDOUT:
 // CHECK:STDOUT: --- fail_import_overloaded_function_decl.carbon
 // CHECK:STDOUT:
 // CHECK:STDOUT: constants {