From c6f2e696958a6eb8c19c0d04dbde0b5c713afb62 Mon Sep 17 00:00:00 2001 From: Dave Lee Date: Thu, 16 Nov 2017 17:46:11 +0000 Subject: [PATCH] Allow empty mappings for optional YAML input Summary: This change fixes a bug where `obj2yaml` can in some cases produce YAML that causes `yaml2obj` to error. The ELF YAML document structure has a `Sections` mapping, which contains three mappings, all of which are optional: `Local`, `Global`, and `Weak.` Any one of these can be missing, but if all three are missing, then `yaml2obj` errors. This change allows YAML input for cases like this one. I have tested this with check-llvm and check-lld, and all tests passed. This change is the result of test failures while working on D39582, which introduces a `DynamicSymbols` mapping, which will be empty at times. Reviewers: compnerd, jakehehrlich, silvas, kledzik, mehdi_amini, pcc Reviewed By: compnerd Subscribers: silvas, llvm-commits Differential Revision: https://reviews.llvm.org/D39908 llvm-svn: 318428 --- llvm/lib/Support/YAMLTraits.cpp | 3 ++- llvm/test/tools/yaml2obj/empty-symbols.yaml | 10 ++++++++++ 2 files changed, 12 insertions(+), 1 deletion(-) create mode 100644 llvm/test/tools/yaml2obj/empty-symbols.yaml diff --git a/llvm/lib/Support/YAMLTraits.cpp b/llvm/lib/Support/YAMLTraits.cpp index 75a2224..a80adfd 100644 --- a/llvm/lib/Support/YAMLTraits.cpp +++ b/llvm/lib/Support/YAMLTraits.cpp @@ -160,7 +160,8 @@ bool Input::preflightKey(const char *Key, bool Required, bool, bool &UseDefault, MapHNode *MN = dyn_cast(CurrentNode); if (!MN) { - setError(CurrentNode, "not a mapping"); + if (Required || !isa(CurrentNode)) + setError(CurrentNode, "not a mapping"); return false; } MN->ValidKeys.push_back(Key); diff --git a/llvm/test/tools/yaml2obj/empty-symbols.yaml b/llvm/test/tools/yaml2obj/empty-symbols.yaml new file mode 100644 index 0000000..1ba37ad --- /dev/null +++ b/llvm/test/tools/yaml2obj/empty-symbols.yaml @@ -0,0 +1,10 @@ +# Ensure yaml2obj doesn't error on empty optional mappings, such as Symbols +# RUN: yaml2obj %s -o %t + +!ELF +FileHeader: + Class: ELFCLASS64 + Data: ELFDATA2LSB + Type: ET_DYN + Machine: EM_X86_64 +Symbols: -- 2.7.4