[Mlir-commits] [mlir] c9ca768 - [mlir][shape] Fix crash when shape.lib array references undefined symbol (#184613)

[llvmlistbot at llvm.org]

Author: Mehdi Amini
Date: 2026-03-04T15:37:02+01:00
New Revision: c9ca768c88cc2bec4240b8710e6d173e7be278e4

URL: https://github.com/llvm/llvm-project/commit/c9ca768c88cc2bec4240b8710e6d173e7be278e4
DIFF: https://github.com/llvm/llvm-project/commit/c9ca768c88cc2bec4240b8710e6d173e7be278e4.diff

LOG: [mlir][shape] Fix crash when shape.lib array references undefined symbol (#184613)

In verifyOperationAttribute(), the single-symbol path for shape.lib used
SymbolTable::lookupSymbolIn() followed by an explicit null check. The
array path at line 196-197 used dyn_cast<FunctionLibraryOp>() directly
on the lookup result, which asserts when the symbol is not found (null
pointer).

Fix: use dyn_cast_or_null<> instead of dyn_cast<> so that a missing
symbol falls through to the existing "does not refer to
FunctionLibraryOp" error diagnostic instead of asserting.

Fixes #159653

Added: 
    

Modified: 
    mlir/lib/Dialect/Shape/IR/Shape.cpp
    mlir/test/Dialect/Shape/invalid.mlir

Removed: 
    


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diff  --git a/mlir/lib/Dialect/Shape/IR/Shape.cpp b/mlir/lib/Dialect/Shape/IR/Shape.cpp
index 4d03b7b2b2064..38cac53be3022 100644
--- a/mlir/lib/Dialect/Shape/IR/Shape.cpp
+++ b/mlir/lib/Dialect/Shape/IR/Shape.cpp
@@ -193,7 +193,7 @@ LogicalResult ShapeDialect::verifyOperationAttribute(Operation *op,
           return op->emitError(
               "only SymbolRefAttr allowed in shape.lib attribute array");
 
-        auto shapeFnLib = dyn_cast<shape::FunctionLibraryOp>(
+        auto shapeFnLib = dyn_cast_or_null<shape::FunctionLibraryOp>(
             SymbolTable::lookupSymbolIn(op, llvm::cast<SymbolRefAttr>(it)));
         if (!shapeFnLib)
           return op->emitError()

diff  --git a/mlir/test/Dialect/Shape/invalid.mlir b/mlir/test/Dialect/Shape/invalid.mlir
index ce2a438d70311..572583edd59bd 100644
--- a/mlir/test/Dialect/Shape/invalid.mlir
+++ b/mlir/test/Dialect/Shape/invalid.mlir
@@ -258,6 +258,14 @@ module attributes {shape.lib = @fn} { }
 
 // -----
 
+// Test that shape function library array entry is defined (regression test for
+// github.com/llvm/llvm-project/issues/159653: dyn_cast crash on missing symbol).
+
+// expected-error at +1 {{@missing does not refer to FunctionLibraryOp}}
+module attributes {shape.lib = [@missing]} { }
+
+// -----
+
 func.func @fn(%arg: !shape.shape) -> !shape.witness {
   // expected-error at +1 {{required at least 2 input shapes}}
   %0 = shape.cstr_broadcastable %arg : !shape.shape