diff --git a/mlir/include/mlir/IR/OpImplementation.h b/mlir/include/mlir/IR/OpImplementation.h
--- a/mlir/include/mlir/IR/OpImplementation.h
+++ b/mlir/include/mlir/IR/OpImplementation.h
@@ -1035,7 +1035,7 @@
   /// Parse an affine expr instance into 'expr' using the already computed
   /// mapping from symbols to affine expressions in 'symbolSet'.
   virtual ParseResult
-  parseAffineExpr(SmallVectorImpl<std::pair<StringRef, AffineExpr>> &symbolSet,
+  parseAffineExpr(ArrayRef<std::pair<StringRef, AffineExpr>> symbolSet,
                   AffineExpr &expr) = 0;
 
   /// Parse an integer set instance into 'set'.
diff --git a/mlir/lib/AsmParser/AffineParser.cpp b/mlir/lib/AsmParser/AffineParser.cpp
--- a/mlir/lib/AsmParser/AffineParser.cpp
+++ b/mlir/lib/AsmParser/AffineParser.cpp
@@ -54,7 +54,7 @@
                                   AffineMap &result);
   ParseResult parseAffineMapOrIntegerSetInline(AffineMap &map, IntegerSet &set);
   ParseResult parseAffineExprInline(
-      SmallVectorImpl<std::pair<StringRef, AffineExpr>> &symbolSet,
+      ArrayRef<std::pair<StringRef, AffineExpr>> symbolSet,
       AffineExpr &expr);
   ParseResult parseIntegerSetConstraints(unsigned numDims, unsigned numSymbols,
                                          IntegerSet &result);
@@ -538,9 +538,9 @@
 
 /// Parse an affine expresion definition inline, with given symbols.
 ParseResult AffineParser::parseAffineExprInline(
-    SmallVectorImpl<std::pair<StringRef, AffineExpr>> &symbolSet,
+    ArrayRef<std::pair<StringRef, AffineExpr>> symbolSet,
     AffineExpr &expr) {
-  dimsAndSymbols.assign(symbolSet);
+  dimsAndSymbols.assign(symbolSet.begin(), symbolSet.end());
   expr = parseAffineExpr();
   return success(expr != nullptr);
 }
@@ -716,7 +716,7 @@
   return success();
 }
 ParseResult Parser::parseAffineExprReference(
-    SmallVectorImpl<std::pair<StringRef, AffineExpr>> &symbolSet,
+    ArrayRef<std::pair<StringRef, AffineExpr>> symbolSet,
     AffineExpr &expr) {
   return AffineParser(state).parseAffineExprInline(symbolSet, expr);
 }
diff --git a/mlir/lib/AsmParser/AsmParserImpl.h b/mlir/lib/AsmParser/AsmParserImpl.h
--- a/mlir/lib/AsmParser/AsmParserImpl.h
+++ b/mlir/lib/AsmParser/AsmParserImpl.h
@@ -459,7 +459,7 @@
   /// Parse an affine expr instance into 'expr' using the already computed
   /// mapping from symbols to affine expressions in 'symbolSet'.
   ParseResult
-  parseAffineExpr(SmallVectorImpl<std::pair<StringRef, AffineExpr>> &symbolSet,
+  parseAffineExpr(ArrayRef<std::pair<StringRef, AffineExpr>> symbolSet,
                   AffineExpr &expr) override {
     return parser.parseAffineExprReference(symbolSet, expr);
   }
diff --git a/mlir/lib/AsmParser/Parser.h b/mlir/lib/AsmParser/Parser.h
--- a/mlir/lib/AsmParser/Parser.h
+++ b/mlir/lib/AsmParser/Parser.h
@@ -301,7 +301,7 @@
                                                   IntegerSet &set);
   ParseResult parseAffineMapReference(AffineMap &map);
   ParseResult parseAffineExprReference(
-      SmallVectorImpl<std::pair<StringRef, AffineExpr>> &symbolSet,
+      ArrayRef<std::pair<StringRef, AffineExpr>> symbolSet,
       AffineExpr &expr);
   ParseResult parseIntegerSetReference(IntegerSet &set);