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tree-sitter / tree-sitter-c

C grammar for tree-sitter
MIT License
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Error in source leads to very tall tree #118

Open casouri opened 1 year ago

casouri commented 1 year ago

I don't know if this is fixable or should be fixed, but in the following snippet, tree-sitter-c generates a very tall tree, which makes recursively traversing the tree very expensive and overflows the call stack. Querying a tall tree is also way slower.

static hf_register_info hf[] = {
#line 1 "./asn1/rrc/packet-rrc-hfarr.c"
   { &hf_rrc_DL_DCCH_Message_PDU,
     { "DL-DCCH-Message", "rrc.DL_DCCH_Message_element",
       FT_NONE, BASE_NONE, NULL, 0,
       NULL, HFILL }},
   { &hf_rrc_cellIdentity_c_id,
      {"Cell Identifier", "rrc.cellIdentity.c_id",
      FT_UINT32, BASE_DEC, NULL, 0,
      "The Cell Identifier (C-Id) part of the Cell Identity", HFILL }}
/* ... and tens of thousands of array initializers. */
 };

Tree-sitter-c considers the closing brackets in, eg, NULL, HFILL}} errors and skips them, turning a ~10k wide tree into a ~10k tall tree.

amaanq commented 1 year ago

It's because of the #line directive, should that be added to the grammar?