Add flag to ignore errors in custom sections (#833)

If a wasm engine fails to parse a custom section, it must not be an
error. In wabt we often won't want to continue if a custom section can't
be parsed, but it still may be useful to be able to continue.

This change adds a new flag `--ignore-custom-section-errors` to
`wasm2wat` and `wasm-validate`, which will partially parse a custom
section with errors. This could lead to some strange behavior (partially
completed data structures), but generally should be safe to do.

See issue #378 and the discussion on pull #830 for more info.

1 files changed, 6 insertions, 1 deletions

diff --git a/src/tools/wasm2wat.cc b/src/tools/wasm2wat.cc
index 89caaf7f..0263f2c5 100644
--- a/src/tools/wasm2wat.cc
+++ b/src/tools/wasm2wat.cc
@@ -41,6 +41,7 @@ static Features s_features;
 static WriteWatOptions s_write_wat_options;
 static bool s_generate_names;
 static bool s_read_debug_names = true;
+static bool s_fail_on_custom_section_error = true;
 static std::unique_ptr<FileStream> s_log_stream;
 static bool s_validate = true;
 
@@ -80,6 +81,9 @@ static void ParseOptions(int argc, char** argv) {
                    []() { s_write_wat_options.inline_import = true; });
   parser.AddOption("no-debug-names", "Ignore debug names in the binary file",
                    []() { s_read_debug_names = false; });
+  parser.AddOption("ignore-custom-section-errors",
+                   "Ignore errors in custom sections",
+                   []() { s_fail_on_custom_section_error = false; });
   parser.AddOption(
       "generate-names",
       "Give auto-generated names to non-named functions, types, etc.",
@@ -107,7 +111,8 @@ int ProgramMain(int argc, char** argv) {
     Module module;
     const bool kStopOnFirstError = true;
     ReadBinaryOptions options(s_features, s_log_stream.get(),
-                              s_read_debug_names, kStopOnFirstError);
+                              s_read_debug_names, kStopOnFirstError,
+                              s_fail_on_custom_section_error);
     result = ReadBinaryIr(s_infile.c_str(), file_data.data(),
                           file_data.size(), &options, &error_handler, &module);
     if (Succeeded(result)) {