[clang] [OpenMP][Clang] Parsing support for num_teams lower bound (PR #180608)

[via cfe-commits]

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@@ -5080,6 +5080,55 @@ bool Parser::ParseOpenMPVarList(OpenMPDirectiveKind DKind,
           Diag(Tok, diag::err_modifier_expected_colon) << "fallback";
       }
     }
+  } // Handle num_teams clause with optional lower-bound:upper-bound syntax
+  if (Kind == OMPC_num_teams && !Tok.is(tok::r_paren) &&
+      !Tok.is(tok::annot_pragma_openmp_end)) {
+    // Look ahead to detect top-level colon
+    TentativeParsingAction TPA(*this);
+    bool HasColon = false;
+    int Depth = 0;
+
+    while (!Tok.is(tok::annot_pragma_openmp_end)) {
+      if (Tok.is(tok::l_paren))
+        Depth++;
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ykhatav wrote:

 I tried removing the depth tracking, but it causes test failures. ParseAssignmentExpression() stops at ":" even when delimiters are unbalanced (e.g.,num_teams((x+1:10) with missing )). Without depth tracking, this gets misparsed as colon syntax instead of reporting the delimiter mismatch error.
My intention of using depth tracking to distinguish valid colon syntax from malformed expressions.
Is there a better way to detect well-formed colon syntax that I'm missing?


https://github.com/llvm/llvm-project/pull/180608