diff --git a/flang/lib/Optimizer/CodeGen/Target.cpp b/flang/lib/Optimizer/CodeGen/Target.cpp
--- a/flang/lib/Optimizer/CodeGen/Target.cpp
+++ b/flang/lib/Optimizer/CodeGen/Target.cpp
@@ -170,6 +170,65 @@
 };
 } // namespace
 
+//===----------------------------------------------------------------------===//
+// i386 (x86 32 bit) Windows target specifics.
+//===----------------------------------------------------------------------===//
+
+namespace {
+struct TargetI386Win : public GenericTarget<TargetI386Win> {
+  using GenericTarget::GenericTarget;
+
+  static constexpr int defaultWidth = 32;
+
+  CodeGenSpecifics::Marshalling
+  complexArgumentType(mlir::Location loc, mlir::Type eleTy) const override {
+    CodeGenSpecifics::Marshalling marshal;
+    // Use a type that will be translated into LLVM as:
+    // { t, t }   struct of 2 eleTy, byval, align 4
+    auto structTy =
+        mlir::TupleType::get(eleTy.getContext(), mlir::TypeRange{eleTy, eleTy});
+    marshal.emplace_back(fir::ReferenceType::get(structTy),
+                         AT{/*align=*/4, /*byval=*/true});
+    return marshal;
+  }
+
+  CodeGenSpecifics::Marshalling
+  complexReturnType(mlir::Location loc, mlir::Type eleTy) const override {
+    CodeGenSpecifics::Marshalling marshal;
+    const auto *sem = &floatToSemantics(kindMap, eleTy);
+    if (sem == &llvm::APFloat::IEEEsingle()) {
+      // i64   pack both floats in a 64-bit GPR
+      marshal.emplace_back(mlir::IntegerType::get(eleTy.getContext(), 64),
+                           AT{});
+    } else if (sem == &llvm::APFloat::IEEEdouble()) {
+      // Use a type that will be translated into LLVM as:
+      // { double, double }   struct of 2 double, sret, align 8
+      marshal.emplace_back(
+          fir::ReferenceType::get(mlir::TupleType::get(
+              eleTy.getContext(), mlir::TypeRange{eleTy, eleTy})),
+          AT{/*align=*/8, /*byval=*/false, /*sret=*/true});
+    } else if (sem == &llvm::APFloat::IEEEquad()) {
+      // Use a type that will be translated into LLVM as:
+      // { fp128, fp128 }   struct of 2 fp128, sret, align 16
+      marshal.emplace_back(
+          fir::ReferenceType::get(mlir::TupleType::get(
+              eleTy.getContext(), mlir::TypeRange{eleTy, eleTy})),
+          AT{/*align=*/16, /*byval=*/false, /*sret=*/true});
+    } else if (sem == &llvm::APFloat::x87DoubleExtended()) {
+      // Use a type that will be translated into LLVM as:
+      // { x86_fp80, x86_fp80 }   struct of 2 x86_fp80, sret, align 4
+      marshal.emplace_back(
+          fir::ReferenceType::get(mlir::TupleType::get(
+              eleTy.getContext(), mlir::TypeRange{eleTy, eleTy})),
+          AT{/*align=*/4, /*byval=*/false, /*sret=*/true});
+    } else {
+      TODO(loc, "complex for this precision");
+    }
+    return marshal;
+  }
+};
+} // namespace
+
 //===----------------------------------------------------------------------===//
 // x86_64 (x86 64 bit) linux target specifics.
 //===----------------------------------------------------------------------===//
@@ -232,6 +291,76 @@
 };
 } // namespace
 
+//===----------------------------------------------------------------------===//
+// x86_64 (x86 64 bit) Windows target specifics.
+//===----------------------------------------------------------------------===//
+
+namespace {
+struct TargetX86_64Win : public GenericTarget<TargetX86_64Win> {
+  using GenericTarget::GenericTarget;
+
+  static constexpr int defaultWidth = 64;
+
+  CodeGenSpecifics::Marshalling
+  complexArgumentType(mlir::Location loc, mlir::Type eleTy) const override {
+    CodeGenSpecifics::Marshalling marshal;
+    const auto *sem = &floatToSemantics(kindMap, eleTy);
+    if (sem == &llvm::APFloat::IEEEsingle()) {
+      // i64   pack both floats in a 64-bit GPR
+      marshal.emplace_back(mlir::IntegerType::get(eleTy.getContext(), 64),
+                           AT{});
+    } else if (sem == &llvm::APFloat::IEEEdouble()) {
+      // Use a type that will be translated into LLVM as:
+      // { double, double }   struct of 2 double, byval, align 8
+      marshal.emplace_back(
+          fir::ReferenceType::get(mlir::TupleType::get(
+              eleTy.getContext(), mlir::TypeRange{eleTy, eleTy})),
+          AT{/*align=*/8, /*byval=*/true});
+    } else if (sem == &llvm::APFloat::IEEEquad() ||
+               sem == &llvm::APFloat::x87DoubleExtended()) {
+      // Use a type that will be translated into LLVM as:
+      // { t, t }   struct of 2 eleTy, byval, align 16
+      marshal.emplace_back(
+          fir::ReferenceType::get(mlir::TupleType::get(
+              eleTy.getContext(), mlir::TypeRange{eleTy, eleTy})),
+          AT{/*align=*/16, /*byval=*/true});
+    } else {
+      TODO(loc, "complex for this precision");
+    }
+    return marshal;
+  }
+
+  CodeGenSpecifics::Marshalling
+  complexReturnType(mlir::Location loc, mlir::Type eleTy) const override {
+    CodeGenSpecifics::Marshalling marshal;
+    const auto *sem = &floatToSemantics(kindMap, eleTy);
+    if (sem == &llvm::APFloat::IEEEsingle()) {
+      // i64   pack both floats in a 64-bit GPR
+      marshal.emplace_back(mlir::IntegerType::get(eleTy.getContext(), 64),
+                           AT{});
+    } else if (sem == &llvm::APFloat::IEEEdouble()) {
+      // Use a type that will be translated into LLVM as:
+      // { double, double }   struct of 2 double, sret, align 8
+      marshal.emplace_back(
+          fir::ReferenceType::get(mlir::TupleType::get(
+              eleTy.getContext(), mlir::TypeRange{eleTy, eleTy})),
+          AT{/*align=*/8, /*byval=*/false, /*sret=*/true});
+    } else if (sem == &llvm::APFloat::IEEEquad() ||
+               sem == &llvm::APFloat::x87DoubleExtended()) {
+      // Use a type that will be translated into LLVM as:
+      // { t, t }   struct of 2 eleTy, sret, align 16
+      marshal.emplace_back(
+          fir::ReferenceType::get(mlir::TupleType::get(
+              eleTy.getContext(), mlir::TypeRange{eleTy, eleTy})),
+          AT{/*align=*/16, /*byval=*/false, /*sret=*/true});
+    } else {
+      TODO(loc, "complex for this precision");
+    }
+    return marshal;
+  }
+};
+} // namespace
+
 //===----------------------------------------------------------------------===//
 // AArch64 linux target specifics.
 //===----------------------------------------------------------------------===//
@@ -545,11 +674,19 @@
   default:
     break;
   case llvm::Triple::ArchType::x86:
-    return std::make_unique<TargetI386>(ctx, std::move(trp),
-                                        std::move(kindMap));
-  case llvm::Triple::ArchType::x86_64:
-    return std::make_unique<TargetX86_64>(ctx, std::move(trp),
+    if (trp.isOSWindows())
+      return std::make_unique<TargetI386Win>(ctx, std::move(trp),
+                                             std::move(kindMap));
+    else
+      return std::make_unique<TargetI386>(ctx, std::move(trp),
                                           std::move(kindMap));
+  case llvm::Triple::ArchType::x86_64:
+    if (trp.isOSWindows())
+      return std::make_unique<TargetX86_64Win>(ctx, std::move(trp),
+                                               std::move(kindMap));
+    else
+      return std::make_unique<TargetX86_64>(ctx, std::move(trp),
+                                            std::move(kindMap));
   case llvm::Triple::ArchType::aarch64:
     return std::make_unique<TargetAArch64>(ctx, std::move(trp),
                                            std::move(kindMap));
diff --git a/flang/test/Fir/target-rewrite-complex.fir b/flang/test/Fir/target-rewrite-complex.fir
--- a/flang/test/Fir/target-rewrite-complex.fir
+++ b/flang/test/Fir/target-rewrite-complex.fir
@@ -1,5 +1,7 @@
 // RUN: fir-opt --target-rewrite="target=i386-unknown-linux-gnu" %s | FileCheck %s --check-prefix=I32
+// RUN: fir-opt --target-rewrite="target=i386-w64-windows-gnu" %s | FileCheck %s --check-prefix=I32_MINGW
 // RUN: fir-opt --target-rewrite="target=x86_64-unknown-linux-gnu" %s | FileCheck %s --check-prefix=X64
+// RUN: fir-opt --target-rewrite="target=x86_64-w64-windows-gnu" %s | FileCheck %s --check-prefix=X64_MINGW
 // RUN: fir-opt --target-rewrite="target=aarch64-unknown-linux-gnu" %s | FileCheck %s --check-prefix=AARCH64
 // RUN: fir-opt --target-rewrite="target=powerpc64le-unknown-linux-gnu" %s | FileCheck %s --check-prefix=PPC64le
 // RUN: fir-opt --target-rewrite="target=sparc64-unknown-linux-gnu" %s | FileCheck %s --check-prefix=SPARCV9
@@ -11,7 +13,9 @@
 // Test that we rewrite the signature and body of a function that returns a
 // complex<4>.
 // I32-LABEL: func @returncomplex4() -> i64
+// I32_MINGW-LABEL: func @returncomplex4() -> i64
 // X64-LABEL: func @returncomplex4() -> !fir.vector<2:!fir.real<4>>
+// X64_MINGW-LABEL: func @returncomplex4() -> i64
 // AARCH64-LABEL: func @returncomplex4() -> tuple<!fir.real<4>, !fir.real<4>>
 // PPC64le-LABEL: func @returncomplex4() -> tuple<!fir.real<4>, !fir.real<4>>
 // SPARCV9-LABEL: func @returncomplex4() -> tuple<!fir.real<4>, !fir.real<4>>
@@ -21,8 +25,12 @@
 func.func @returncomplex4() -> !fir.complex<4> {
   // I32: fir.insert_value
   // I32: [[VAL:%[0-9A-Za-z]+]] = fir.insert_value
+  // I32_MINGW: fir.insert_value
+  // I32_MINGW: [[VAL:%[0-9A-Za-z]+]] = fir.insert_value
   // X64: fir.insert_value
   // X64: [[VAL:%[0-9A-Za-z]+]] = fir.insert_value
+  // X64_MINGW: fir.insert_value
+  // X64_MINGW: [[VAL:%[0-9A-Za-z]+]] = fir.insert_value
   // AARCH64: fir.insert_value
   // AARCH64: [[VAL:%[0-9A-Za-z]+]] = fir.insert_value
   // PPC64le: fir.insert_value
@@ -49,11 +57,21 @@
   // I32: fir.store [[VAL]] to [[ADDRC]] : !fir.ref<!fir.complex<4>>
   // I32: [[RES:%[0-9A-Za-z]+]] = fir.load [[ADDRI64]] : !fir.ref<i64>
   // I32: return [[RES]] : i64
+  // I32_MINGW: [[ADDRV:%[0-9A-Za-z]+]] = fir.alloca i64
+  // I32_MINGW: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRV]] : (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // I32_MINGW: fir.store [[VAL]] to [[ADDRC]] : !fir.ref<!fir.complex<4>>
+  // I32_MINGW: [[RES:%[0-9A-Za-z]+]] = fir.load [[ADDRV]] : !fir.ref<i64>
+  // I32_MINGW: return [[RES]] : i64
   // X64: [[ADDRV:%[0-9A-Za-z]+]] = fir.alloca !fir.vector<2:!fir.real<4>>
   // X64: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRV]] : (!fir.ref<!fir.vector<2:!fir.real<4>>>) -> !fir.ref<!fir.complex<4>>
   // X64: fir.store [[VAL]] to [[ADDRC]] : !fir.ref<!fir.complex<4>>
   // X64: [[RES:%[0-9A-Za-z]+]] = fir.load [[ADDRV]] : !fir.ref<!fir.vector<2:!fir.real<4>>>
   // X64: return [[RES]] : !fir.vector<2:!fir.real<4>>
+  // X64_MINGW: [[ADDRV:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRV]] : (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // X64_MINGW: fir.store [[VAL]] to [[ADDRC]] : !fir.ref<!fir.complex<4>>
+  // X64_MINGW: [[RES:%[0-9A-Za-z]+]] = fir.load [[ADDRV]] : !fir.ref<i64>
+  // X64_MINGW: return [[RES]] : i64
   // AARCH64: [[ADDRT:%[0-9A-Za-z]+]] = fir.alloca tuple<!fir.real<4>, !fir.real<4>>
   // AARCH64: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRT]] : (!fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) -> !fir.ref<!fir.complex<4>>
   // AARCH64: fir.store [[VAL]] to [[ADDRC]] : !fir.ref<!fir.complex<4>>
@@ -85,7 +103,11 @@
 // complex<8>.
 // I32-LABEL:func @returncomplex8
 // I32-SAME: ([[ARG0:%[0-9A-Za-z]+]]: !fir.ref<tuple<!fir.real<8>, !fir.real<8>>>  {llvm.align = 4 : i32, llvm.sret = tuple<!fir.real<8>, !fir.real<8>>})
+// I32_MINGW-LABEL: func @returncomplex8
+// I32_MINGW-SAME: ([[ARG0:%[0-9A-Za-z]+]]: !fir.ref<tuple<!fir.real<8>, !fir.real<8>>>  {llvm.align = 8 : i32, llvm.sret = tuple<!fir.real<8>, !fir.real<8>>})
 // X64-LABEL: func @returncomplex8() -> tuple<!fir.real<8>, !fir.real<8>>
+// X64_MINGW-LABEL: func @returncomplex8
+// X64_MINGW-SAME: ([[ARG0:%[0-9A-Za-z]+]]: !fir.ref<tuple<!fir.real<8>, !fir.real<8>>>  {llvm.align = 8 : i32, llvm.sret = tuple<!fir.real<8>, !fir.real<8>>})
 // AARCH64-LABEL: func @returncomplex8() -> tuple<!fir.real<8>, !fir.real<8>>
 // PPC64le-LABEL: func @returncomplex8() -> tuple<!fir.real<8>, !fir.real<8>>
 // SPARCV9-LABEL: func @returncomplex8() -> tuple<!fir.real<8>, !fir.real<8>>
@@ -95,8 +117,12 @@
 func.func @returncomplex8() -> !fir.complex<8> {
   // I32: fir.insert_value
   // I32: [[VAL:%[0-9A-Za-z]+]] = fir.insert_value {{.*}}
+  // I32_MINGW: fir.insert_value
+  // I32_MINGW: [[VAL:%[0-9A-Za-z]+]] = fir.insert_value {{.*}}
   // X64: fir.insert_value
   // X64: [[VAL:%[0-9A-Za-z]+]] = fir.insert_value {{.*}}
+  // X64_MINGW: fir.insert_value
+  // X64_MINGW: [[VAL:%[0-9A-Za-z]+]] = fir.insert_value {{.*}}
   // AARCH64: fir.insert_value
   // AARCH64: [[VAL:%[0-9A-Za-z]+]] = fir.insert_value {{.*}}
   // PPC64le: fir.insert_value
@@ -120,11 +146,17 @@
   // I32: [[ADDR:%[0-9A-Za-z]+]] = fir.convert [[ARG0]] : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> !fir.ref<!fir.complex<8>>
   // I32: fir.store [[VAL]] to [[ADDR]] : !fir.ref<!fir.complex<8>>
   // I32: return{{ *$}}
+  // I32_MINGW: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ARG0]] : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> !fir.ref<!fir.complex<8>>
+  // I32_MINGW: fir.store [[VAL]] to [[ADDRC]] : !fir.ref<!fir.complex<8>>
+  // I32_MINGW: return
   // X64: [[ADDRT:%[0-9A-Za-z]+]] = fir.alloca tuple<!fir.real<8>, !fir.real<8>>
   // X64: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRT]] : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> !fir.ref<!fir.complex<8>>
   // X64: fir.store [[VAL]] to [[ADDRC]] : !fir.ref<!fir.complex<8>>
   // X64: [[RES:%[0-9A-Za-z]+]] = fir.load [[ADDRT]] : !fir.ref<tuple<!fir.real<8>, !fir.real<8>>>
   // X64: return [[RES]] : tuple<!fir.real<8>, !fir.real<8>>
+  // X64_MINGW: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ARG0]] : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> !fir.ref<!fir.complex<8>>
+  // X64_MINGW: fir.store [[VAL]] to [[ADDRC]] : !fir.ref<!fir.complex<8>>
+  // X64_MINGW: return
   // AARCH64: [[ADDRT:%[0-9A-Za-z]+]] = fir.alloca tuple<!fir.real<8>, !fir.real<8>>
   // AARCH64: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRT]] : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> !fir.ref<!fir.complex<8>>
   // AARCH64: fir.store [[VAL]] to [[ADDRC]] : !fir.ref<!fir.complex<8>>
@@ -160,7 +192,9 @@
 
 // Test that we rewrite the signature of a function that accepts a complex<4>.
 // I32-LABEL: func private @paramcomplex4(!fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>})
+// I32_MINGW-LABEL: func private @paramcomplex4(!fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>})
 // X64-LABEL: func private @paramcomplex4(!fir.vector<2:!fir.real<4>>)
+// X64_MINGW-LABEL: func private @paramcomplex4(i64)
 // AARCH64-LABEL: func private @paramcomplex4(!fir.array<2x!fir.real<4>>)
 // PPC64le-LABEL: func private @paramcomplex4(!fir.real<4>, !fir.real<4>)
 // SPARCV9-LABEL: func private @paramcomplex4(!fir.real<4>, !fir.real<4>)
@@ -171,7 +205,9 @@
 
 // Test that we rewrite calls to functions that return or accept complex<4>.
 // I32-LABEL: func @callcomplex4
+// I32_MINGW-LABEL: func @callcomplex4
 // X64-LABEL: func @callcomplex4
+// X64_MINGW-LABEL: func @callcomplex4
 // AARCH64-LABEL: func @callcomplex4
 // PPC64le-LABEL: func @callcomplex4
 // SPARCV9-LABEL: func @callcomplex4
@@ -181,7 +217,9 @@
 func.func @callcomplex4(%arg0 : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) {
 
   // I32: [[RES:%[0-9A-Za-z]+]] = fir.call @returncomplex4() : () -> i64
+  // I32_MINGW: [[RES:%[0-9A-Za-z]+]] = fir.call @returncomplex4() : () -> i64
   // X64: [[RES:%[0-9A-Za-z]+]] = fir.call @returncomplex4() : () -> !fir.vector<2:!fir.real<4>>
+  // X64_MINGW: [[RES:%[0-9A-Za-z]+]] = fir.call @returncomplex4() : () -> i64
   // AARCH64: [[RES:%[0-9A-Za-z]+]] = fir.call @returncomplex4() : () -> tuple<!fir.real<4>, !fir.real<4>>
   // PPC64le: [[RES:%[0-9A-Za-z]+]] = fir.call @returncomplex4() : () -> tuple<!fir.real<4>, !fir.real<4>>
   // SPARCV9: [[RES:%[0-9A-Za-z]+]] = fir.call @returncomplex4() : () -> tuple<!fir.real<4>, !fir.real<4>>
@@ -199,6 +237,15 @@
   // I32: [[T:%[0-9A-Za-z]+]] = fir.convert [[ADDRC2]] : (!fir.ref<!fir.complex<4>>) -> !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>
   // I32: fir.call @paramcomplex4([[T]]) : (!fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) -> ()
 
+  // I32_MINGW: [[ADDRI64:%[0-9A-Za-z]+]] = fir.alloca i64
+  // I32_MINGW: fir.store [[RES]] to [[ADDRI64]] : !fir.ref<i64>
+  // I32_MINGW: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRI64]] : (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // I32_MINGW: [[C:%[0-9A-Za-z]+]] = fir.load [[ADDRC]] : !fir.ref<!fir.complex<4>>
+  // I32_MINGW: [[ADDRC2:%[0-9A-Za-z]+]] = fir.alloca !fir.complex<4>
+  // I32_MINGW: fir.store [[C]] to [[ADDRC2]] : !fir.ref<!fir.complex<4>>
+  // I32_MINGW: [[T:%[0-9A-Za-z]+]] = fir.convert [[ADDRC2]] : (!fir.ref<!fir.complex<4>>) -> !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>
+  // I32_MINGW: fir.call @paramcomplex4([[T]]) : (!fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) -> ()
+
   // X64: [[ADDRV:%[0-9A-Za-z]+]] = fir.alloca !fir.vector<2:!fir.real<4>>
   // X64: fir.store [[RES]] to [[ADDRV]] : !fir.ref<!fir.vector<2:!fir.real<4>>>
   // X64: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRV]] : (!fir.ref<!fir.vector<2:!fir.real<4>>>) -> !fir.ref<!fir.complex<4>>
@@ -209,6 +256,16 @@
   // X64: [[VRELOADED:%[0-9A-Za-z]+]] = fir.load [[ADDRV2]] : !fir.ref<!fir.vector<2:!fir.real<4>>>
   // X64: fir.call @paramcomplex4([[VRELOADED]]) : (!fir.vector<2:!fir.real<4>>) -> ()
 
+  // X64_MINGW: [[ADDRV:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW: fir.store [[RES]] to [[ADDRV]] : !fir.ref<i64>
+  // X64_MINGW: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRV]] :  (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // X64_MINGW: [[V:%[0-9A-Za-z]+]] = fir.load [[ADDRC]] : !fir.ref<!fir.complex<4>>
+  // X64_MINGW: [[ADDRV2:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW: [[ADDRC2:%[0-9A-Za-z]+]] = fir.convert [[ADDRV2]] : (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // X64_MINGW: fir.store [[V]] to [[ADDRC2]] : !fir.ref<!fir.complex<4>>
+  // X64_MINGW: [[VRELOADED:%[0-9A-Za-z]+]] = fir.load [[ADDRV2]] : !fir.ref<i64>
+  // X64_MINGW: fir.call @paramcomplex4([[VRELOADED]]) : (i64) -> ()
+
   // AARCH64: [[ADDRT:%[0-9A-Za-z]+]] = fir.alloca tuple<!fir.real<4>, !fir.real<4>>
   // AARCH64: fir.store [[RES]] to [[ADDRT]] : !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>
   // AARCH64: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRT]] : (!fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) -> !fir.ref<!fir.complex<4>>
@@ -261,7 +318,9 @@
   fir.call @paramcomplex4(%1) : (!fir.complex<4>) -> ()
 
   // I32: [[RES:%[0-9A-Za-z]+]] = fir.dispatch "ret_complex"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) -> i64 {pass_arg_pos = 0 : i32}
+  // I32_MINGW: [[RES:%[0-9A-Za-z]+]] = fir.dispatch "ret_complex"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) -> i64 {pass_arg_pos = 0 : i32}
   // X64: [[RES:%[0-9A-Za-z]+]] = fir.dispatch "ret_complex"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) -> !fir.vector<2:!fir.real<4>> {pass_arg_pos = 0 : i32}
+  // X64_MINGW: [[RES:%[0-9A-Za-z]+]] = fir.dispatch "ret_complex"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) -> i64 {pass_arg_pos = 0 : i32}
   // AARCH64: [[RES:%[0-9A-Za-z]+]] = fir.dispatch "ret_complex"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) -> tuple<!fir.real<4>, !fir.real<4>> {pass_arg_pos = 0 : i32}
   // PPC64le: [[RES:%[0-9A-Za-z]+]] = fir.dispatch "ret_complex"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) -> tuple<!fir.real<4>, !fir.real<4>> {pass_arg_pos = 0 : i32}
   // SPARCV9: [[RES:%[0-9A-Za-z]+]] = fir.dispatch "ret_complex"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) -> tuple<!fir.real<4>, !fir.real<4>> {pass_arg_pos = 0 : i32}
@@ -277,6 +336,15 @@
   // I32: [[T:%[0-9A-Za-z]+]] = fir.convert [[ADDRC2]] : (!fir.ref<!fir.complex<4>>) -> !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>
   // I32: fir.dispatch "with_complex"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}}, [[T]] : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>, !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) {pass_arg_pos = 0 : i32}
 
+  // I32_MINGW: [[ADDRI64:%[0-9A-Za-z]+]] = fir.alloca i64
+  // I32_MINGW: fir.store [[RES]] to [[ADDRI64]] : !fir.ref<i64>
+  // I32_MINGW: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRI64]] : (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // I32_MINGW: [[C:%[0-9A-Za-z]+]] = fir.load [[ADDRC]] : !fir.ref<!fir.complex<4>>
+  // I32_MINGW: [[ADDRC2:%[0-9A-Za-z]+]] = fir.alloca !fir.complex<4>
+  // I32_MINGW: fir.store [[C]] to [[ADDRC2]] : !fir.ref<!fir.complex<4>>
+  // I32_MINGW: [[T:%[0-9A-Za-z]+]] = fir.convert [[ADDRC2]] : (!fir.ref<!fir.complex<4>>) -> !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>
+  // I32_MINGW: fir.dispatch "with_complex"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}}, [[T]] : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>, !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) {pass_arg_pos = 0 : i32}
+
   // X64: [[ADDRV:%[0-9A-Za-z]+]] = fir.alloca !fir.vector<2:!fir.real<4>>
   // X64: fir.store [[RES]] to [[ADDRV]] : !fir.ref<!fir.vector<2:!fir.real<4>>>
   // X64: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRV]] : (!fir.ref<!fir.vector<2:!fir.real<4>>>) -> !fir.ref<!fir.complex<4>>
@@ -287,6 +355,16 @@
   // X64: [[VRELOADED:%[0-9A-Za-z]+]] = fir.load [[ADDRV2]] : !fir.ref<!fir.vector<2:!fir.real<4>>>
   // X64: fir.dispatch "with_complex"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}}, [[VRELOADED]] : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>, !fir.vector<2:!fir.real<4>>) {pass_arg_pos = 0 : i32}
 
+  // X64_MINGW: [[ADDRV:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW: fir.store [[RES]] to [[ADDRV]] : !fir.ref<i64>
+  // X64_MINGW: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRV]] : (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // X64_MINGW: [[V:%[0-9A-Za-z]+]] = fir.load [[ADDRC]] : !fir.ref<!fir.complex<4>>
+  // X64_MINGW: [[ADDRV2:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW: [[ADDRC2:%[0-9A-Za-z]+]] = fir.convert [[ADDRV2]] : (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // X64_MINGW: fir.store [[V]] to [[ADDRC2]] : !fir.ref<!fir.complex<4>>
+  // X64_MINGW: [[VRELOADED:%[0-9A-Za-z]+]] = fir.load [[ADDRV2]] : !fir.ref<i64>
+  // X64_MINGW: fir.dispatch "with_complex"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}}, [[VRELOADED]] : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>, i64) {pass_arg_pos = 0 : i32}
+
   // AARCH64: [[ADDRT:%[0-9A-Za-z]+]] = fir.alloca tuple<!fir.real<4>, !fir.real<4>>
   // AARCH64: fir.store [[RES]] to [[ADDRT]] : !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>
   // AARCH64: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRT]] : (!fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) -> !fir.ref<!fir.complex<4>>
@@ -324,7 +402,9 @@
 
 
   // I32: fir.dispatch "with_complex2"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}}, %{{.*}} : !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>, !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) {pass_arg_pos = 1 : i32}
+  // I32_MINGW: fir.dispatch "with_complex2"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}}, %{{.*}} : !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>, !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) {pass_arg_pos = 1 : i32}
   // X64: fir.dispatch "with_complex2"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}}, %{{.*}} : !fir.vector<2:!fir.real<4>>, !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) {pass_arg_pos = 1 : i32}
+  // X64_MINGW: fir.dispatch "with_complex2"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}}, %{{.*}} : i64, !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) {pass_arg_pos = 1 : i32}
   // AARCH64: fir.dispatch "with_complex2"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}}, %{{.*}} : !fir.array<2x!fir.real<4>>, !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) {pass_arg_pos = 1 : i32}
   // PPC64le: fir.dispatch "with_complex2"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}}, %{{.*}}, %{{.*}} : !fir.real<4>, !fir.real<4>, !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) {pass_arg_pos = 2 : i32}
   // SPARCV9: fir.dispatch "with_complex2"(%{{.*}} : !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) (%{{.*}}, %{{.*}}, %{{.*}} : !fir.real<4>, !fir.real<4>, !fir.class<!fir.type<_QMpolymorphic_testTp1{a:i32,b:i32}>>) {pass_arg_pos = 2 : i32}
@@ -338,7 +418,9 @@
 
 // Test that we rewrite the signature of a function that accepts a complex<8>.
 // I32-LABEL: func private @paramcomplex8(!fir.ref<tuple<!fir.real<8>, !fir.real<8>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<8>, !fir.real<8>>})
+// I32_MINGW-LABEL: func private @paramcomplex8(!fir.ref<tuple<!fir.real<8>, !fir.real<8>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<8>, !fir.real<8>>})
 // X64-LABEL: func private @paramcomplex8(!fir.real<8>, !fir.real<8>)
+// X64_MINGW-LABEL: func private @paramcomplex8(!fir.ref<tuple<!fir.real<8>, !fir.real<8>>> {llvm.align = 8 : i32, llvm.byval = tuple<!fir.real<8>, !fir.real<8>>})
 // AARCH64-LABEL: func private @paramcomplex8(!fir.array<2x!fir.real<8>>)
 // PPC64le-LABEL: func private @paramcomplex8(!fir.real<8>, !fir.real<8>)
 // SPARCV9-LABEL: func private @paramcomplex8(!fir.real<8>, !fir.real<8>)
@@ -349,7 +431,9 @@
 
 // Test that we rewrite calls to functions that return or accept complex<8>.
 // I32-LABEL: func @callcomplex8()
+// I32_MINGW-LABEL: func @callcomplex8()
 // X64-LABEL: func @callcomplex8()
+// X64_MINGW-LABEL: func @callcomplex8()
 // AARCH64-LABEL: func @callcomplex8()
 // PPC64le-LABEL: func @callcomplex8()
 // SPARCV9-LABEL: func @callcomplex8()
@@ -359,7 +443,11 @@
 func.func @callcomplex8() {
   // I32: [[RES:%[0-9A-Za-z]+]] = fir.alloca tuple<!fir.real<8>, !fir.real<8>>
   // I32: fir.call @returncomplex8([[RES]]) : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> ()
+  // I32_MINGW: [[RES:%[0-9A-Za-z]+]] = fir.alloca tuple<!fir.real<8>, !fir.real<8>>
+  // I32_MINGW: fir.call @returncomplex8([[RES]]) : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> ()
   // X64: [[RES:%[0-9A-Za-z]+]] = fir.call @returncomplex8() : () -> tuple<!fir.real<8>, !fir.real<8>>
+  // X64_MINGW: [[RES:%[0-9A-Za-z]+]] = fir.alloca tuple<!fir.real<8>, !fir.real<8>>
+  // X64_MINGW: fir.call @returncomplex8([[RES]]) : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> ()
   // AARCH64: [[RES:%[0-9A-Za-z]+]] = fir.call @returncomplex8() : () -> tuple<!fir.real<8>, !fir.real<8>>
   // PPC64le: [[RES:%[0-9A-Za-z]+]] = fir.call @returncomplex8() : () -> tuple<!fir.real<8>, !fir.real<8>>
   // SPARCV9: [[RES:%[0-9A-Za-z]+]] = fir.call @returncomplex8() : () -> tuple<!fir.real<8>, !fir.real<8>>
@@ -375,6 +463,13 @@
   // I32: [[ADDRT:%[0-9A-Za-z]+]] = fir.convert [[ADDRC]] : (!fir.ref<!fir.complex<8>>) -> !fir.ref<tuple<!fir.real<8>, !fir.real<8>>>
   // I32: fir.call @paramcomplex8([[ADDRT]]) : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> ()
 
+  // I32_MINGW: [[RESC:%[0-9A-Za-z]+]] = fir.convert [[RES]] : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> !fir.ref<!fir.complex<8>>
+  // I32_MINGW: [[V:%[0-9A-Za-z]+]]  = fir.load [[RESC]] : !fir.ref<!fir.complex<8>>
+  // I32_MINGW: [[ADDRC:%[0-9A-Za-z]+]] = fir.alloca !fir.complex<8>
+  // I32_MINGW: fir.store [[V]] to [[ADDRC]] : !fir.ref<!fir.complex<8>>
+  // I32_MINGW: [[ADDRT:%[0-9A-Za-z]+]] = fir.convert [[ADDRC]] : (!fir.ref<!fir.complex<8>>) -> !fir.ref<tuple<!fir.real<8>, !fir.real<8>>>
+  // I32_MINGW: fir.call @paramcomplex8([[ADDRT]]) : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> ()
+
   // X64: [[ADDRT:%[0-9A-Za-z]+]] = fir.alloca tuple<!fir.real<8>, !fir.real<8>>
   // X64: fir.store [[RES]] to [[ADDRT]] : !fir.ref<tuple<!fir.real<8>, !fir.real<8>>>
   // X64: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRT]] : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> !fir.ref<!fir.complex<8>>
@@ -383,6 +478,13 @@
   // X64: [[B:%[0-9A-Za-z]+]] = fir.extract_value [[V]], [1 : i32] : (!fir.complex<8>) -> !fir.real<8>
   // X64: fir.call @paramcomplex8([[A]], [[B]]) : (!fir.real<8>, !fir.real<8>) -> ()
 
+  // X64_MINGW: [[RESC:%[0-9A-Za-z]+]] = fir.convert [[RES]] : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> !fir.ref<!fir.complex<8>>
+  // X64_MINGW: [[V:%[0-9A-Za-z]+]]  = fir.load [[RESC]] : !fir.ref<!fir.complex<8>>
+  // X64_MINGW: [[ADDRC:%[0-9A-Za-z]+]] = fir.alloca !fir.complex<8>
+  // X64_MINGW: fir.store [[V]] to [[ADDRC]] : !fir.ref<!fir.complex<8>>
+  // X64_MINGW: [[ADDRT:%[0-9A-Za-z]+]] = fir.convert [[ADDRC]] : (!fir.ref<!fir.complex<8>>) -> !fir.ref<tuple<!fir.real<8>, !fir.real<8>>>
+  // X64_MINGW: fir.call @paramcomplex8([[ADDRT]]) : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> ()
+
   // AARCH64: [[ADDRT:%[0-9A-Za-z]+]] = fir.alloca tuple<!fir.real<8>, !fir.real<8>>
   // AARCH64: fir.store [[RES]] to [[ADDRT]] : !fir.ref<tuple<!fir.real<8>, !fir.real<8>>>
   // AARCH64: [[ADDRV:%[0-9A-Za-z]+]] = fir.convert [[ADDRT]] : (!fir.ref<tuple<!fir.real<8>, !fir.real<8>>>) -> !fir.ref<!fir.complex<8>>
@@ -439,7 +541,9 @@
 
 // Test multiple complex<4> parameters and arguments
 // I32-LABEL: func private @calleemultipleparamscomplex4(!fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>}, !fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>}, !fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>})
+// I32_MINGW-LABEL: func private @calleemultipleparamscomplex4(!fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>}, !fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>}, !fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>})
 // X64-LABEL: func private @calleemultipleparamscomplex4(!fir.vector<2:!fir.real<4>>, !fir.vector<2:!fir.real<4>>, !fir.vector<2:!fir.real<4>>)
+// X64_MINGW-LABEL: func private @calleemultipleparamscomplex4(i64, i64, i64)
 // AARCH64-LABEL: func private @calleemultipleparamscomplex4(!fir.array<2x!fir.real<4>>, !fir.array<2x!fir.real<4>>, !fir.array<2x!fir.real<4>>)
 // PPC64le-LABEL: func private @calleemultipleparamscomplex4(!fir.real<4>, !fir.real<4>, !fir.real<4>, !fir.real<4>, !fir.real<4>, !fir.real<4>)
 // SPARCV9-LABEL: func private @calleemultipleparamscomplex4(!fir.real<4>, !fir.real<4>, !fir.real<4>, !fir.real<4>, !fir.real<4>, !fir.real<4>)
@@ -450,8 +554,12 @@
 
 // I32-LABEL: func @multipleparamscomplex4
 // I32-SAME: ([[Z1:%[0-9A-Za-z]+]]: !fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>}, [[Z2:%[0-9A-Za-z]+]]: !fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>}, [[Z3:%[0-9A-Za-z]+]]: !fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>})
+// I32_MINGW-LABEL: func @multipleparamscomplex4
+// I32_MINGW-SAME: ([[Z1:%[0-9A-Za-z]+]]: !fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>}, [[Z2:%[0-9A-Za-z]+]]: !fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>}, [[Z3:%[0-9A-Za-z]+]]: !fir.ref<tuple<!fir.real<4>, !fir.real<4>>> {llvm.align = 4 : i32, llvm.byval = tuple<!fir.real<4>, !fir.real<4>>})
 // X64-LABEL: func @multipleparamscomplex4
 // X64-SAME: ([[Z1:%[0-9A-Za-z]+]]: !fir.vector<2:!fir.real<4>>, [[Z2:%[0-9A-Za-z]+]]: !fir.vector<2:!fir.real<4>>, [[Z3:%[0-9A-Za-z]+]]: !fir.vector<2:!fir.real<4>>)
+// X64_MINGW-LABEL: func @multipleparamscomplex4
+// X64_MINGW-SAME: ([[Z1:%[0-9A-Za-z]+]]: i64, [[Z2:%[0-9A-Za-z]+]]: i64, [[Z3:%[0-9A-Za-z]+]]: i64)
 // AARCH64-LABEL: func @multipleparamscomplex4
 // AARCH64-SAME: ([[Z1:%[0-9A-Za-z]+]]: !fir.array<2x!fir.real<4>>, [[Z2:%[0-9A-Za-z]+]]: !fir.array<2x!fir.real<4>>, [[Z3:%[0-9A-Za-z]+]]: !fir.array<2x!fir.real<4>>)
 // PPC64le-LABEL: func @multipleparamscomplex4
@@ -484,6 +592,25 @@
 
   // I32: fir.call @calleemultipleparamscomplex4([[Z1_ADDRT]], [[Z2_ADDRT]], [[Z3_ADDRT]]) : (!fir.ref<tuple<!fir.real<4>, !fir.real<4>>>, !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>, !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) -> ()
 
+  // I32_MINGW-DAG: [[Z1_ADDR:%[0-9A-Za-z]+]] = fir.convert [[Z1]] : (!fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) -> !fir.ref<!fir.complex<4>>
+  // I32_MINGW-DAG: [[Z1_VAL:%[0-9A-Za-z]+]] = fir.load [[Z1_ADDR]] : !fir.ref<!fir.complex<4>>
+  // I32_MINGW-DAG: [[Z2_ADDR:%[0-9A-Za-z]+]] = fir.convert [[Z2]] : (!fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) -> !fir.ref<!fir.complex<4>>
+  // I32_MINGW-DAG: [[Z2_VAL:%[0-9A-Za-z]+]] = fir.load [[Z2_ADDR]] : !fir.ref<!fir.complex<4>>
+  // I32_MINGW-DAG: [[Z3_ADDR:%[0-9A-Za-z]+]] = fir.convert [[Z3]] : (!fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) -> !fir.ref<!fir.complex<4>>
+  // I32_MINGW-DAG: [[Z3_VAL:%[0-9A-Za-z]+]] = fir.load [[Z3_ADDR]] : !fir.ref<!fir.complex<4>>
+
+  // I32_MINGW-DAG: [[Z1_ADDRC:%[0-9A-Za-z]+]] = fir.alloca !fir.complex<4>
+  // I32_MINGW-DAG: fir.store [[Z1_VAL]] to [[Z1_ADDRC]] : !fir.ref<!fir.complex<4>>
+  // I32_MINGW-DAG: [[Z1_ADDRT:%[0-9A-Za-z]+]] = fir.convert [[Z1_ADDRC]] : (!fir.ref<!fir.complex<4>>) -> !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>
+  // I32_MINGW-DAG: [[Z2_ADDRC:%[0-9A-Za-z]+]] = fir.alloca !fir.complex<4>
+  // I32_MINGW-DAG: fir.store [[Z2_VAL]] to [[Z2_ADDRC]] : !fir.ref<!fir.complex<4>>
+  // I32_MINGW-DAG: [[Z2_ADDRT:%[0-9A-Za-z]+]] = fir.convert [[Z2_ADDRC]] : (!fir.ref<!fir.complex<4>>) -> !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>
+  // I32_MINGW-DAG: [[Z3_ADDRC:%[0-9A-Za-z]+]] = fir.alloca !fir.complex<4>
+  // I32_MINGW-DAG: fir.store [[Z3_VAL]] to [[Z3_ADDRC]] : !fir.ref<!fir.complex<4>>
+  // I32_MINGW-DAG: [[Z3_ADDRT:%[0-9A-Za-z]+]] = fir.convert [[Z3_ADDRC]] : (!fir.ref<!fir.complex<4>>) -> !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>
+
+  // I32_MINGW: fir.call @calleemultipleparamscomplex4([[Z1_ADDRT]], [[Z2_ADDRT]], [[Z3_ADDRT]]) : (!fir.ref<tuple<!fir.real<4>, !fir.real<4>>>, !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>, !fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) -> ()
+
   // X64-DAG: [[Z3_ADDR:%[0-9A-Za-z]+]] = fir.alloca !fir.vector<2:!fir.real<4>>
   // X64-DAG: fir.store [[Z3]] to [[Z3_ADDR]] : !fir.ref<!fir.vector<2:!fir.real<4>>>
   // X64-DAG: [[Z3_ADDRC:%[0-9A-Za-z]+]] = fir.convert [[Z3_ADDR]] : (!fir.ref<!fir.vector<2:!fir.real<4>>>) -> !fir.ref<!fir.complex<4>>
@@ -512,6 +639,34 @@
 
   // X64: fir.call @calleemultipleparamscomplex4([[Z1_RELOADED]], [[Z2_RELOADED]], [[Z3_RELOADED]]) : (!fir.vector<2:!fir.real<4>>, !fir.vector<2:!fir.real<4>>, !fir.vector<2:!fir.real<4>>) -> ()
 
+  // X64_MINGW-DAG: [[Z3_ADDR:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW-DAG: fir.store [[Z3]] to [[Z3_ADDR]] : !fir.ref<i64>
+  // X64_MINGW-DAG: [[Z3_ADDRC:%[0-9A-Za-z]+]] = fir.convert [[Z3_ADDR]] : (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // X64_MINGW-DAG: [[Z3_VAL:%[0-9A-Za-z]+]] = fir.load [[Z3_ADDRC]] : !fir.ref<!fir.complex<4>>
+  // X64_MINGW-DAG: [[Z2_ADDR:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW-DAG: fir.store [[Z2]] to [[Z2_ADDR]] : !fir.ref<i64>
+  // X64_MINGW-DAG: [[Z2_ADDRC:%[0-9A-Za-z]+]] = fir.convert [[Z2_ADDR]] : (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // X64_MINGW-DAG: [[Z2_VAL:%[0-9A-Za-z]+]] = fir.load [[Z2_ADDRC]] : !fir.ref<!fir.complex<4>>
+  // X64_MINGW-DAG: [[Z1_ADDR:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW-DAG: fir.store [[Z1]] to [[Z1_ADDR]] : !fir.ref<i64>
+  // X64_MINGW-DAG: [[Z1_ADDRC:%[0-9A-Za-z]+]] = fir.convert [[Z1_ADDR]] : (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // X64_MINGW-DAG: [[Z1_VAL:%[0-9A-Za-z]+]] = fir.load [[Z1_ADDRC]] : !fir.ref<!fir.complex<4>>
+
+  // X64_MINGW-DAG: [[Z1_ADDRV:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW-DAG: [[Z1_ADDRC2:%[0-9A-Za-z]+]] = fir.convert [[Z1_ADDRV]] : (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // X64_MINGW-DAG: fir.store [[Z1_VAL]] to [[Z1_ADDRC2]] : !fir.ref<!fir.complex<4>>
+  // X64_MINGW-DAG: [[Z1_RELOADED:%[0-9A-Za-z]+]] = fir.load [[Z1_ADDRV]] : !fir.ref<i64>
+  // X64_MINGW-DAG: [[Z2_ADDRV:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW-DAG: [[Z2_ADDRC2:%[0-9A-Za-z]+]] = fir.convert [[Z2_ADDRV]] : (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // X64_MINGW-DAG: fir.store [[Z2_VAL]] to [[Z2_ADDRC2]] : !fir.ref<!fir.complex<4>>
+  // X64_MINGW-DAG: [[Z2_RELOADED:%[0-9A-Za-z]+]] = fir.load [[Z2_ADDRV]] : !fir.ref<i64>
+  // X64_MINGW-DAG: [[Z3_ADDRV:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW-DAG: [[Z3_ADDRC2:%[0-9A-Za-z]+]] = fir.convert [[Z3_ADDRV]] : (!fir.ref<i64>) -> !fir.ref<!fir.complex<4>>
+  // X64_MINGW-DAG: fir.store [[Z3_VAL]] to [[Z3_ADDRC2]] : !fir.ref<!fir.complex<4>>
+  // X64_MINGW-DAG: [[Z3_RELOADED:%[0-9A-Za-z]+]] = fir.load [[Z3_ADDRV]] : !fir.ref<i64>
+
+  // X64_MINGW: fir.call @calleemultipleparamscomplex4([[Z1_RELOADED]], [[Z2_RELOADED]], [[Z3_RELOADED]]) : (i64, i64, i64) -> ()
+
   // AARCH64-DAG: [[Z3_ARR:%[0-9A-Za-z]+]] = fir.alloca !fir.array<2x!fir.real<4>>
   // AARCH64-DAG: fir.store [[Z3]] to [[Z3_ARR]] : !fir.ref<!fir.array<2x!fir.real<4>>>
   // AARCH64-DAG: [[Z3_ADDRC:%[0-9A-Za-z]+]] = fir.convert [[Z3_ARR]] : (!fir.ref<!fir.array<2x!fir.real<4>>>) -> !fir.ref<!fir.complex<4>>
@@ -642,9 +797,15 @@
 // I32-LABEL: func private @mlircomplexf32
 // I32-SAME: ([[Z1:%[0-9A-Za-z]+]]: !fir.ref<tuple<f32, f32>> {llvm.align = 4 : i32, llvm.byval = tuple<f32, f32>}, [[Z2:%[0-9A-Za-z]+]]: !fir.ref<tuple<f32, f32>> {llvm.align = 4 : i32, llvm.byval = tuple<f32, f32>})
 // I32-SAME: -> i64
+// I32_MINGW-LABEL: func private @mlircomplexf32
+// I32_MINGW-SAME: ([[Z1:%[0-9A-Za-z]+]]: !fir.ref<tuple<f32, f32>> {llvm.align = 4 : i32, llvm.byval = tuple<f32, f32>}, [[Z2:%[0-9A-Za-z]+]]: !fir.ref<tuple<f32, f32>> {llvm.align = 4 : i32, llvm.byval = tuple<f32, f32>})
+// I32_MINGW-SAME: -> i64
 // X64-LABEL: func private @mlircomplexf32
 // X64-SAME: ([[Z1:%[0-9A-Za-z]+]]: !fir.vector<2:f32>, [[Z2:%[0-9A-Za-z]+]]: !fir.vector<2:f32>)
 // X64-SAME: -> !fir.vector<2:f32>
+// X64_MINGW-LABEL: func private @mlircomplexf32
+// X64_MINGW-SAME: ([[Z1:%[0-9A-Za-z]+]]: i64, [[Z2:%[0-9A-Za-z]+]]: i64)
+// X64_MINGW-SAME: -> i64
 // AARCH64-LABEL: func private @mlircomplexf32
 // AARCH64-SAME: ([[Z1:%[0-9A-Za-z]+]]: !fir.array<2xf32>, [[Z2:%[0-9A-Za-z]+]]: !fir.array<2xf32>)
 // AARCH64-SAME: -> tuple<f32, f32>
@@ -679,6 +840,20 @@
 
   // I32: [[VAL:%[0-9A-Za-z]+]] = fir.call @mlircomplexf32([[Z1_ADDRT]], [[Z2_ADDRT]]) : (!fir.ref<tuple<f32, f32>>, !fir.ref<tuple<f32, f32>>) -> i64
 
+  // I32_MINGW-DAG: [[Z1_ADDR:%[0-9A-Za-z]+]] = fir.convert [[Z1]] : (!fir.ref<tuple<f32, f32>>) -> !fir.ref<complex<f32>>
+  // I32_MINGW-DAG: [[Z1_VAL:%[0-9A-Za-z]+]] = fir.load [[Z1_ADDR]] : !fir.ref<complex<f32>>
+  // I32_MINGW-DAG: [[Z2_ADDR:%[0-9A-Za-z]+]] = fir.convert [[Z2]] : (!fir.ref<tuple<f32, f32>>) -> !fir.ref<complex<f32>>
+  // I32_MINGW-DAG: [[Z2_VAL:%[0-9A-Za-z]+]] = fir.load [[Z2_ADDR]] : !fir.ref<complex<f32>>
+
+  // I32_MINGW-DAG: [[Z1_ADDRC:%[0-9A-Za-z]+]] = fir.alloca complex<f32>
+  // I32_MINGW-DAG: fir.store [[Z1_VAL]] to [[Z1_ADDRC]] : !fir.ref<complex<f32>>
+  // I32_MINGW-DAG: [[Z1_ADDRT:%[0-9A-Za-z]+]] = fir.convert [[Z1_ADDRC]] : (!fir.ref<complex<f32>>) -> !fir.ref<tuple<f32, f32>>
+  // I32_MINGW-DAG: [[Z2_ADDRC:%[0-9A-Za-z]+]] = fir.alloca complex<f32>
+  // I32_MINGW-DAG: fir.store [[Z2_VAL]] to [[Z2_ADDRC]] : !fir.ref<complex<f32>>
+  // I32_MINGW-DAG: [[Z2_ADDRT:%[0-9A-Za-z]+]] = fir.convert [[Z2_ADDRC]] : (!fir.ref<complex<f32>>) -> !fir.ref<tuple<f32, f32>>
+
+  // I32_MINGW: [[VAL:%[0-9A-Za-z]+]] = fir.call @mlircomplexf32([[Z1_ADDRT]], [[Z2_ADDRT]]) : (!fir.ref<tuple<f32, f32>>, !fir.ref<tuple<f32, f32>>) -> i64
+
   // X64-DAG: [[Z2_ADDR:%[0-9A-Za-z]+]] = fir.alloca !fir.vector<2:f32>
   // X64-DAG: fir.store [[Z2]] to [[Z2_ADDR]] : !fir.ref<!fir.vector<2:f32>>
   // X64-DAG: [[Z2_ADDRC:%[0-9A-Za-z]+]] = fir.convert [[Z2_ADDR]] : (!fir.ref<!fir.vector<2:f32>>) -> !fir.ref<complex<f32>>
@@ -699,6 +874,26 @@
 
   // X64: [[VAL:%[0-9A-Za-z]+]] = fir.call @mlircomplexf32([[Z1_RELOADED]], [[Z2_RELOADED]]) : (!fir.vector<2:f32>, !fir.vector<2:f32>) -> !fir.vector<2:f32>
 
+  // X64_MINGW-DAG: [[Z2_ADDR:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW-DAG: fir.store [[Z2]] to [[Z2_ADDR]] : !fir.ref<i64>
+  // X64_MINGW-DAG: [[Z2_ADDRC:%[0-9A-Za-z]+]] = fir.convert [[Z2_ADDR]] : (!fir.ref<i64>) -> !fir.ref<complex<f32>>
+  // X64_MINGW-DAG: [[Z2_VAL:%[0-9A-Za-z]+]] = fir.load [[Z2_ADDRC]] : !fir.ref<complex<f32>>
+  // X64_MINGW-DAG: [[Z1_ADDR:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW-DAG: fir.store [[Z1]] to [[Z1_ADDR]] : !fir.ref<i64>
+  // X64_MINGW-DAG: [[Z1_ADDRC:%[0-9A-Za-z]+]] = fir.convert [[Z1_ADDR]] : (!fir.ref<i64>) -> !fir.ref<complex<f32>>
+  // X64_MINGW-DAG: [[Z1_VAL:%[0-9A-Za-z]+]] = fir.load [[Z1_ADDRC]] : !fir.ref<complex<f32>>
+
+  // X64_MINGW-DAG: [[Z1_ADDRV:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW-DAG: [[Z1_ADDRC2:%[0-9A-Za-z]+]] = fir.convert [[Z1_ADDRV]] : (!fir.ref<i64>) -> !fir.ref<complex<f32>>
+  // X64_MINGW-DAG: fir.store [[Z1_VAL]] to [[Z1_ADDRC2]] : !fir.ref<complex<f32>>
+  // X64_MINGW-DAG: [[Z1_RELOADED:%[0-9A-Za-z]+]] = fir.load [[Z1_ADDRV]] : !fir.ref<i64>
+  // X64_MINGW-DAG: [[Z2_ADDRV:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW-DAG: [[Z2_ADDRC2:%[0-9A-Za-z]+]] = fir.convert [[Z2_ADDRV]] : (!fir.ref<i64>) -> !fir.ref<complex<f32>>
+  // X64_MINGW-DAG: fir.store [[Z2_VAL]] to [[Z2_ADDRC2]] : !fir.ref<complex<f32>>
+  // X64_MINGW-DAG: [[Z2_RELOADED:%[0-9A-Za-z]+]] = fir.load [[Z2_ADDRV]] : !fir.ref<i64>
+
+  // X64_MINGW: [[VAL:%[0-9A-Za-z]+]] = fir.call @mlircomplexf32([[Z1_RELOADED]], [[Z2_RELOADED]]) : (i64, i64) -> i64
+
   // AARCH64-DAG: [[Z2_ARR:%[0-9A-Za-z]+]] = fir.alloca !fir.array<2xf32>
   // AARCH64-DAG: fir.store [[Z2]] to [[Z2_ARR]] : !fir.ref<!fir.array<2xf32>>
   // AARCH64-DAG: [[Z2_ADDRC:%[0-9A-Za-z]+]] = fir.convert [[Z2_ARR]] : (!fir.ref<!fir.array<2xf32>>) -> !fir.ref<complex<f32>>
@@ -800,6 +995,16 @@
   // I32: [[RES:%[0-9A-Za-z]+]] = fir.load [[ADDRI64_2]] : !fir.ref<i64>
   // I32: return [[RES]] : i64
 
+  // I32_MINGW: [[ADDRI64:%[0-9A-Za-z]+]] = fir.alloca i64
+  // I32_MINGW: fir.store [[VAL]] to [[ADDRI64]] : !fir.ref<i64>
+  // I32_MINGW: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRI64]] : (!fir.ref<i64>) -> !fir.ref<complex<f32>>
+  // I32_MINGW: [[VAL_2:%[0-9A-Za-z]+]] = fir.load [[ADDRC]] : !fir.ref<complex<f32>>
+  // I32_MINGW: [[ADDRI64_2:%[0-9A-Za-z]+]] = fir.alloca i64
+  // I32_MINGW: [[ADDRC_2:%[0-9A-Za-z]+]] = fir.convert [[ADDRI64_2]] : (!fir.ref<i64>) -> !fir.ref<complex<f32>>
+  // I32_MINGW: fir.store [[VAL_2]] to [[ADDRC_2]] : !fir.ref<complex<f32>>
+  // I32_MINGW: [[RES:%[0-9A-Za-z]+]] = fir.load [[ADDRI64_2]] : !fir.ref<i64>
+  // I32_MINGW: return [[RES]] : i64
+
   // X64: [[ADDRV:%[0-9A-Za-z]+]] = fir.alloca !fir.vector<2:f32>
   // X64: fir.store [[VAL]] to [[ADDRV]] : !fir.ref<!fir.vector<2:f32>>
   // X64: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRV]] : (!fir.ref<!fir.vector<2:f32>>) -> !fir.ref<complex<f32>>
@@ -810,6 +1015,16 @@
   // X64: [[RES:%[0-9A-Za-z]+]] = fir.load [[ADDRV_2]] : !fir.ref<!fir.vector<2:f32>>
   // X64: return [[RES]] : !fir.vector<2:f32>
 
+  // X64_MINGW: [[ADDRV:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW: fir.store [[VAL]] to [[ADDRV]] : !fir.ref<i64>
+  // X64_MINGW: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRV]] : (!fir.ref<i64>) -> !fir.ref<complex<f32>>
+  // X64_MINGW: [[V:%[0-9A-Za-z]+]] = fir.load [[ADDRC]] : !fir.ref<complex<f32>>
+  // X64_MINGW: [[ADDRV_2:%[0-9A-Za-z]+]] = fir.alloca i64
+  // X64_MINGW: [[ADDRC_2:%[0-9A-Za-z]+]] = fir.convert [[ADDRV_2]] : (!fir.ref<i64>) -> !fir.ref<complex<f32>>
+  // X64_MINGW: fir.store [[V]] to [[ADDRC_2]] : !fir.ref<complex<f32>>
+  // X64_MINGW: [[RES:%[0-9A-Za-z]+]] = fir.load [[ADDRV_2]] : !fir.ref<i64>
+  // X64_MINGW: return [[RES]] : i64
+
   // AARCH64: [[ADDRT:%[0-9A-Za-z]+]] = fir.alloca tuple<f32, f32>
   // AARCH64: fir.store [[VAL]] to [[ADDRT]] : !fir.ref<tuple<f32, f32>>
   // AARCH64: [[ADDRC:%[0-9A-Za-z]+]] = fir.convert [[ADDRT]] : (!fir.ref<tuple<f32, f32>>) -> !fir.ref<complex<f32>>
@@ -874,7 +1089,9 @@
 
 // Test that we rewrite the fir.address_of operator.
 // I32-LABEL: func @addrof()
+// I32_MINGW-LABEL: func @addrof()
 // X64-LABEL: func @addrof()
+// X64_MINGW-LABEL: func @addrof()
 // AARCH64-LABEL: func @addrof()
 // PPC64le-LABEL: func @addrof()
 // SPARCV9-LABEL: func @addrof()
@@ -883,7 +1100,9 @@
 // LOONGARCH64-LABEL: func @addrof()
 func.func @addrof() {
   // I32: {{%.*}} = fir.address_of(@returncomplex4) : () -> i64
+  // I32_MINGW: {{%.*}} = fir.address_of(@returncomplex4) : () -> i64
   // X64: {{%.*}} = fir.address_of(@returncomplex4) : () -> !fir.vector<2:!fir.real<4>>
+  // X64_MINGW: {{%.*}} = fir.address_of(@returncomplex4) : () -> i64
   // AARCH64: {{%.*}} = fir.address_of(@returncomplex4) : () -> tuple<!fir.real<4>, !fir.real<4>>
   // PPC64le: {{%.*}} = fir.address_of(@returncomplex4) : () -> tuple<!fir.real<4>, !fir.real<4>>
   // RISCV64: {{%.*}} = fir.address_of(@returncomplex4) : () -> tuple<!fir.real<4>, !fir.real<4>>
@@ -892,7 +1111,9 @@
   %r = fir.address_of(@returncomplex4) : () -> !fir.complex<4>
 
   // I32: {{%.*}} = fir.address_of(@paramcomplex4) : (!fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) -> ()
+  // I32_MINGW: {{%.*}} = fir.address_of(@paramcomplex4) : (!fir.ref<tuple<!fir.real<4>, !fir.real<4>>>) -> ()
   // X64: {{%.*}} = fir.address_of(@paramcomplex4) : (!fir.vector<2:!fir.real<4>>) -> ()
+  // X64_MINGW: {{%.*}} = fir.address_of(@paramcomplex4) : (i64) -> ()
   // AARCH64: {{%.*}} = fir.address_of(@paramcomplex4) : (!fir.array<2x!fir.real<4>>) -> ()
   // PPC64le: {{%.*}} = fir.address_of(@paramcomplex4) : (!fir.real<4>, !fir.real<4>) -> ()
   // SPARCV9: {{%.*}} = fir.address_of(@paramcomplex4) : (!fir.real<4>, !fir.real<4>) -> ()