[Mlir-commits] [mlir] [mlir] Silence warnings on Windows (PR #191557)

[Alexandre Ganea]

https://github.com/aganea created https://github.com/llvm/llvm-project/pull/191557

MSVC STL4037 deprecates std::complex with non-floating-point element types.

This fixes:
```
warning: 'complex' is deprecated: warning STL4037: ...
```

>From 4e521b5e9eaa967895e203dae1fbf4423ec05195 Mon Sep 17 00:00:00 2001
From: Alexandre Ganea <aganea at havenstudios.com>
Date: Fri, 10 Apr 2026 18:07:39 -0400
Subject: [PATCH] [mlir] Silence warnings on Windows

MSVC STL4037 deprecates std::complex with non-floating-point element types.

This fixes:
```
warning: 'complex' is deprecated: warning STL4037: ...
```
---
 mlir/include/mlir/Dialect/Complex/IR/Complex.h | 5 +++++
 mlir/include/mlir/IR/BuiltinAttributes.h       | 7 +++++++
 mlir/lib/IR/BuiltinAttributes.cpp              | 3 +++
 mlir/unittests/IR/AttributeTest.cpp            | 7 +++++++
 4 files changed, 22 insertions(+)

diff --git a/mlir/include/mlir/Dialect/Complex/IR/Complex.h b/mlir/include/mlir/Dialect/Complex/IR/Complex.h
index be7e50d656385..9793d315ce217 100644
--- a/mlir/include/mlir/Dialect/Complex/IR/Complex.h
+++ b/mlir/include/mlir/Dialect/Complex/IR/Complex.h
@@ -15,6 +15,7 @@
 #include "mlir/IR/OpImplementation.h"
 #include "mlir/Interfaces/InferTypeOpInterface.h"
 #include "mlir/Interfaces/SideEffectInterfaces.h"
+#include "llvm/Support/Compiler.h"
 
 //===----------------------------------------------------------------------===//
 // Complex Dialect
@@ -35,7 +36,11 @@
 #define GET_OP_CLASSES
 #include "mlir/Dialect/Complex/IR/ComplexOps.h.inc"
 
+// std::complex<APFloat> is a non-standard instantiation that triggers
+// MSVC STL4037 deprecation warnings in the generated attribute code.
+LLVM_SUPPRESS_DEPRECATED_DECLARATIONS_PUSH
 #define GET_ATTRDEF_CLASSES
 #include "mlir/Dialect/Complex/IR/ComplexAttributes.h.inc"
+LLVM_SUPPRESS_DEPRECATED_DECLARATIONS_POP
 
 #endif // MLIR_DIALECT_COMPLEX_IR_COMPLEX_H_
diff --git a/mlir/include/mlir/IR/BuiltinAttributes.h b/mlir/include/mlir/IR/BuiltinAttributes.h
index 1f805882db276..00c5d70d14a03 100644
--- a/mlir/include/mlir/IR/BuiltinAttributes.h
+++ b/mlir/include/mlir/IR/BuiltinAttributes.h
@@ -12,6 +12,7 @@
 #include "mlir/IR/BuiltinAttributeInterfaces.h"
 #include "llvm/ADT/APFloat.h"
 #include "llvm/ADT/Sequence.h"
+#include "llvm/Support/Compiler.h"
 #include <complex>
 #include <optional>
 
@@ -294,6 +295,10 @@ class DenseElementsAttr : public Attribute {
     size_t bitWidth;
   };
 
+  // std::complex<APInt> and std::complex<APFloat> are non-standard
+  // instantiations that trigger MSVC STL4037 deprecation warnings.
+  LLVM_SUPPRESS_DEPRECATED_DECLARATIONS_PUSH
+
   /// A utility iterator that allows walking over the internal raw complex APInt
   /// values.
   class ComplexIntElementIterator
@@ -358,6 +363,8 @@ class DenseElementsAttr : public Attribute {
     const llvm::fltSemantics *smt;
   };
 
+  LLVM_SUPPRESS_DEPRECATED_DECLARATIONS_POP
+
   //===--------------------------------------------------------------------===//
   // Value Querying
   //===--------------------------------------------------------------------===//
diff --git a/mlir/lib/IR/BuiltinAttributes.cpp b/mlir/lib/IR/BuiltinAttributes.cpp
index c06ae5b178624..682cebcc7188a 100644
--- a/mlir/lib/IR/BuiltinAttributes.cpp
+++ b/mlir/lib/IR/BuiltinAttributes.cpp
@@ -6,6 +6,8 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Support/Compiler.h"
+LLVM_SUPPRESS_DEPRECATED_DECLARATIONS_PUSH
 #include "mlir/IR/BuiltinAttributes.h"
 #include "AttributeDetail.h"
 #include "mlir/IR/AffineMap.h"
@@ -1698,3 +1700,4 @@ AffineMap mlir::makeStridedLinearLayoutMap(ArrayRef<int64_t> strides,
 
   return AffineMap::get(strides.size(), nSymbols, expr);
 }
+LLVM_SUPPRESS_DEPRECATED_DECLARATIONS_POP
diff --git a/mlir/unittests/IR/AttributeTest.cpp b/mlir/unittests/IR/AttributeTest.cpp
index 900cacabd592e..934429c9903f9 100644
--- a/mlir/unittests/IR/AttributeTest.cpp
+++ b/mlir/unittests/IR/AttributeTest.cpp
@@ -10,6 +10,7 @@
 #include "mlir/IR/Builders.h"
 #include "mlir/IR/BuiltinAttributes.h"
 #include "mlir/IR/BuiltinTypes.h"
+#include "llvm/Support/Compiler.h"
 #include "gtest/gtest.h"
 #include <optional>
 
@@ -198,21 +199,27 @@ TEST(DenseComplexTest, ComplexFloatSplat) {
 TEST(DenseComplexTest, ComplexIntSplat) {
   MLIRContext context;
   ComplexType complexType = ComplexType::get(IntegerType::get(&context, 64));
+  LLVM_SUPPRESS_DEPRECATED_DECLARATIONS_PUSH
   std::complex<int64_t> value(10, 15);
+  LLVM_SUPPRESS_DEPRECATED_DECLARATIONS_POP
   testSplat(complexType, value);
 }
 
 TEST(DenseComplexTest, ComplexAPFloatSplat) {
   MLIRContext context;
   ComplexType complexType = ComplexType::get(Float32Type::get(&context));
+  LLVM_SUPPRESS_DEPRECATED_DECLARATIONS_PUSH
   std::complex<APFloat> value(APFloat(10.0f), APFloat(15.0f));
+  LLVM_SUPPRESS_DEPRECATED_DECLARATIONS_POP
   testSplat(complexType, value);
 }
 
 TEST(DenseComplexTest, ComplexAPIntSplat) {
   MLIRContext context;
   ComplexType complexType = ComplexType::get(IntegerType::get(&context, 64));
+  LLVM_SUPPRESS_DEPRECATED_DECLARATIONS_PUSH
   std::complex<APInt> value(APInt(64, 10), APInt(64, 15));
+  LLVM_SUPPRESS_DEPRECATED_DECLARATIONS_POP
   testSplat(complexType, value);
 }