segfault during parsing @ pkg/parser/memo_parser.go:66

[Mackenzie Starr]

Hello,
I'm really excited about this project and have been following it for a bit.

I wanted to report a segfault I ran into following the most recent README.md instructions @ 995f59e. It's very possible its operator error or misconfiguration on my part but I figured I would share in the event that it is helpful to you. If it is not helpful, feel free to close since the last thing I want is making you chase a bug without enough context.

thanks for all your efforts here,
Mackenzie

console output:

$ bazel run //:gazelle

Target //:gazelle up-to-date:
  bazel-bin/gazelle-runner.bash
  bazel-bin/gazelle
INFO: Elapsed time: 6.194s, Critical Path: 0.01s
INFO: 1 process: 1 internal.
INFO: Build completed successfully, 1 total action
INFO: Build completed successfully, 1 total action
gazelle: warning: error while setting up final scope: scala.* package not found (some builtin symbols may not resolve!)
resolving dependencies [==================================================>] 894/894 packages

$ bazel run //:gazelle
Target //:gazelle up-to-date:
  bazel-bin/gazelle-runner.bash
  bazel-bin/gazelle
INFO: Elapsed time: 3.631s, Critical Path: 0.01s
INFO: 1 process: 1 internal.
INFO: Build completed successfully, 1 total action
INFO: Build completed successfully, 1 total action
gazelle: Parsed //<redacted> (8 files, 350ms)
gazelle: Parsed //<redacted> (1 files, 21ms)
gazelle: Parsed //<redacted> (2 files, 20ms)
gazelle: Parsed //<redacted> (1 files, 14ms)
gazelle: Parsed //<redacted> (1 files, 43ms)
gazelle: Parsed //<redacted> (1 files, 22ms)
gazelle: Parsed //<redacted> (1 files, 16ms)
gazelle: Parsed //<redacted> (1 files, 24ms)
gazelle: Parsed //<redacted> (1 files, 26ms) 
gazelle: Parsed //<redacted> (1 files, 22ms)
gazelle: Parsed //<redacted> (1 files, 11ms)
gazelle: Parsed //<redacted> (1 files, 2ms)
gazelle: Parsed //<redacted> (1 files, 1ms)
gazelle: Parsed //<redacted> (1 files, 11ms)
gazelle: Parsed //<redacted> (1 files, 2ms)
gazelle: Parsed //<redacted> (1 files, 4ms)
gazelle: Parsed //<redacted> (1 files, 8ms)
gazelle: Parsed //<redacted> (1 files, 4ms)
gazelle: Parsed //<redacted> (1 files, 3ms)
gazelle: Parsed //<redacted> (1 files, 2ms)
gazelle: Parsed //<redacted> (1 files, 14ms)
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x68 pc=0xa62fd9]

goroutine 1 [running]:
github.com/stackb/scala-gazelle/pkg/parser.(*MemoParser).ParseScalaRule(0xc00000e888, {0xc0005c8060, 0xc}, {{0x0, 0x0}, {0xc0005b61b0, 0x14}, {0xc0005c8071, 0x4}, 0x0}, ...)
        external/build_stack_scala_gazelle/pkg/parser/memo_parser.go:66 +0x299
github.com/stackb/scala-gazelle/language/scala.(*scalaPackage).ParseRule(0xc0004cfcb0, 0xc000593680, {0xbda55a, 0x4})
        external/build_stack_scala_gazelle/language/scala/scala_package.go:187 +0x416
github.com/stackb/scala-gazelle/language/scala.(*existingScalaRuleProvider).ResolveRule(0xa783a2?, 0xc00048b500, {0xed2840, 0xc0004cfcb0}, 0xc000593680)
        external/build_stack_scala_gazelle/language/scala/existing_scala_rule.go:70 +0x5e
github.com/stackb/scala-gazelle/language/scala.(*scalaPackage).resolveRule(0xc0004cfcb0, 0xc00048b500, 0xc0004d8341?)
        external/build_stack_scala_gazelle/language/scala/scala_package.go:170 +0x1af
github.com/stackb/scala-gazelle/language/scala.(*scalaPackage).generateRules(0xc0004cfcb0, 0x0?)
        external/build_stack_scala_gazelle/language/scala/scala_package.go:130 +0x37c
github.com/stackb/scala-gazelle/language/scala.newScalaPackage({0xc0005b61b0, 0x14}, 0xc0005cfd60, 0xc0004ce5a0, {0xed7e90?, 0xc000010328}, {0xed5790?, 0xc00000e888}, {0xedd938, 0xc0003a06c0})
        external/build_stack_scala_gazelle/language/scala/scala_package.go:60 +0x175
github.com/stackb/scala-gazelle/language/scala.(*scalaLang).GenerateRules(0xc0003a06c0, {0xc000d35080, {0xc000d84540, 0x34}, {0xc0005b61b0, 0x14}, 0xc0005cfd60, {0xc000d93500, 0x2, 0x2}, ...})
        external/build_stack_scala_gazelle/language/scala/generate.go:28 +0x1b4
main.runFixUpdate.func1({0xc000d84540, 0x34}, {0xc0005b61b0, 0x14}, 0xc000d35080, 0xd8?, 0xc0005cfd60, {0xc000d93500, 0x2, 0x2}, ...)
        external/bazel_gazelle/cmd/gazelle/fix-update.go:298 +0x1078
github.com/bazelbuild/bazel-gazelle/walk.Walk.func1(0xc00070f340, {0xc000d84540, 0x34}, {0xc0005b61b0, 0x14}, 0x1)
        external/bazel_gazelle/walk/walk.go:179 +0x5df
github.com/bazelbuild/bazel-gazelle/walk.Walk.func1(0xc0000f36b0, {0xc000816ab0, 0x24}, {0xc000989ce0, 0x4}, 0x1)
        external/bazel_gazelle/walk/walk.go:172 +0x7d0
github.com/bazelbuild/bazel-gazelle/walk.Walk.func1(0xc0000f36b0, {0xc00003f7c0, 0x1f}, {0x0, 0x0}, 0x0)
        external/bazel_gazelle/walk/walk.go:172 +0x7d0
github.com/bazelbuild/bazel-gazelle/walk.Walk(0xc0000f36b0, {0xc00004ca80?, 0x8, 0x8}, {0xc000363220, 0x1, 0x1}, 0x0, 0xc000121598)
        external/bazel_gazelle/walk/walk.go:182 +0x25a
main.runFixUpdate({0xc00004009a, 0x1f}, 0x7ffdae0d8dba?, {0xc0000320a0, 0x2, 0x2})
        external/bazel_gazelle/cmd/gazelle/fix-update.go:275 +0x6cb
main.run({0xc00004009a?, 0x1f?}, {0xc000032090?, 0x3?, 0x3?})
        external/bazel_gazelle/cmd/gazelle/gazelle.go:95 +0x1f3
main.main()
        external/bazel_gazelle/cmd/gazelle/gazelle.go:72 +0xdd

[Paul Cody Johnston]

Thanks @mackenziestarr it's still early days, it should certainly not panic like this. Will fix.