Bug #20322: rb_enc_interned_str_cstr doesn't accept null pointer for encoding

• Status: Closed
• Assignee: -
• Target version: -
• Backport: 3.0: REQUIRED, 3.1: REQUIRED, 3.2: REQUIRED, 3.3: REQUIRED

[thomasmarshall (Thomas Marshall)]

The header documentation for rb_enc_interned_str_cstr notes:

enc can be a null pointer.

When adding support for this function to TruffleRuby we noticed that the behaviour did not match that documentation. I think this did work previously, but it currently causes a segmentation fault when trying to autoload the encoding because it calls rb_enc_mbmaxlen which expects a non-null encoding.

I'm not sure how important this behaviour is, whether extensions ever actually call this with a null pointer, or if the documentation is instead just incorrect. I think it's a straightforward fix to make the behaviour match the documentation, so I would like to open a PR, but also happy to just remove the note if that is preferable.

[byroot (Jean Boussier)]

That's a regression and should be fixed mostly for consistency with other functions that take a encoding pointer.

[thomasmarshall (Thomas Marshall)]

I opened a PR to fix this: https://github.com/ruby/ruby/pull/10169

[nobu (Nobuyoshi Nakada)]

• Related to Bug #18772: Backport edf01d4e82d8e44ee30ec41fbcb7f802bc8b8c5d added

[nobu (Nobuyoshi Nakada)]

• Backport changed from 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN to 3.0: REQUIRED, 3.1: REQUIRED, 3.2: REQUIRED, 3.3: REQUIRED

[thomasmarshall (Thomas Marshall)]

• Status changed from Open to Closed

Applied in changeset git|7e4b1f8e1935a10df3c41ee60ca0987d73281126.

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[Bug #20322] Fix rb_enc_interned_str_cstr null encoding

The documentation for rb_enc_interned_str_cstr notes that enc can be
a null pointer, but this currently causes a segmentation fault when
trying to autoload the encoding. This commit fixes the issue by checking
for NULL before calling rb_enc_autoload.