[Darwin][IR] Don't error on target_variant mismatch when linking IR (#92297)

Change the ModuleFlag type for target_variant to warning to avoid error
out when the value is different. This matches the linker behavior when
linking object files.

rdar://125874272

5 files changed, 46 insertions, 4 deletions

diff --git a/clang/test/CodeGen/darwin-target-variant.c b/clang/test/CodeGen/darwin-target-variant.c
index 36caaae..9f4b36a 100644
--- a/clang/test/CodeGen/darwin-target-variant.c
+++ b/clang/test/CodeGen/darwin-target-variant.c
@@ -2,5 +2,5 @@
 
 // CHECK: !llvm.module.flags = !{!0, !1, !2
 // CHECK: !0 = !{i32 2, !"SDK Version", [2 x i32] [i32 11, i32 1]}
-// CHECK: !1 = !{i32 4, !"darwin.target_variant.triple", !"x86_64-apple-ios14-macabi"}
+// CHECK: !1 = !{i32 2, !"darwin.target_variant.triple", !"x86_64-apple-ios14-macabi"}
 // CHECK: !2 = !{i32 2, !"darwin.target_variant.SDK Version", [2 x i32] [i32 14, i32 1]}
diff --git a/llvm/lib/IR/Module.cpp b/llvm/lib/IR/Module.cpp
index a8696ed..f97dd18 100644
--- a/llvm/lib/IR/Module.cpp
+++ b/llvm/lib/IR/Module.cpp
@@ -882,7 +882,7 @@ StringRef Module::getDarwinTargetVariantTriple() const {
 }
 
 void Module::setDarwinTargetVariantTriple(StringRef T) {
-  addModuleFlag(ModFlagBehavior::Override, "darwin.target_variant.triple",
+  addModuleFlag(ModFlagBehavior::Warning, "darwin.target_variant.triple",
                 MDString::get(getContext(), T));
 }
 
diff --git a/llvm/test/Linker/darwin-target-variant.ll b/llvm/test/Linker/darwin-target-variant.ll
new file mode 100644
index 0000000..7d46b2d
--- /dev/null
+++ b/llvm/test/Linker/darwin-target-variant.ll
@@ -0,0 +1,42 @@
+; RUN: rm -rf %t && split-file %s %t
+; RUN: llvm-link %t/1.ll %t/2.ll -S -o - | FileCheck %s
+; CHECK: {i32 2, !"darwin.target_variant.triple", !"x86_64-apple-ios13.1-macabi"}
+
+; RUN: llvm-link %t/1.ll %t/old.ll -S -o - | FileCheck %s -check-prefix OLD
+; OLD: {i32 4, !"darwin.target_variant.triple", !"x86_64-apple-ios14.0-macabi"}
+
+;--- 1.ll
+target triple = "x86_64-apple-macos10.15";
+!llvm.module.flags = !{!0, !1, !2};
+!0 = !{i32 2, !"SDK Version", [3 x i32] [ i32 10, i32 15, i32 1 ] };
+!1 = !{i32 2, !"darwin.target_variant.triple", !"x86_64-apple-ios13.1-macabi"};
+!2 = !{i32 2, !"darwin.target_variant.SDK Version", [2 x i32] [ i32 13, i32 2 ] };
+
+define void @foo() {
+entry:
+  ret void
+}
+
+;--- 2.ll
+target triple = "x86_64-apple-macos10.15";
+!llvm.module.flags = !{!0, !1, !2};
+!0 = !{i32 2, !"SDK Version", [3 x i32] [ i32 10, i32 15, i32 1 ] };
+!1 = !{i32 2, !"darwin.target_variant.triple", !"x86_64-apple-ios14.0-macabi"};
+!2 = !{i32 2, !"darwin.target_variant.SDK Version", [2 x i32] [ i32 13, i32 2 ] };
+
+define void @bar() {
+entry:
+  ret void
+}
+
+;--- old.ll
+target triple = "x86_64-apple-macos10.15";
+!llvm.module.flags = !{!0, !1, !2};
+!0 = !{i32 2, !"SDK Version", [3 x i32] [ i32 10, i32 15, i32 1 ] };
+!1 = !{i32 4, !"darwin.target_variant.triple", !"x86_64-apple-ios14.0-macabi"};
+!2 = !{i32 2, !"darwin.target_variant.SDK Version", [2 x i32] [ i32 13, i32 2 ] };
+
+define void @old() {
+entry:
+  ret void
+}
diff --git a/llvm/test/MC/MachO/darwin-target-variant-reverse.ll b/llvm/test/MC/MachO/darwin-target-variant-reverse.ll
index 6d51cd8..fd527b2 100644
--- a/llvm/test/MC/MachO/darwin-target-variant-reverse.ll
+++ b/llvm/test/MC/MachO/darwin-target-variant-reverse.ll
@@ -3,7 +3,7 @@
 target triple = "x86_64-apple-ios13.1-macabi";
 !llvm.module.flags = !{!0, !1, !2};
 !0 = !{i32 2, !"SDK Version", [2 x i32] [ i32 13, i32 1 ] };
-!1 = !{i32 1, !"darwin.target_variant.triple", !"x86_64-apple-macos10.15"};
+!1 = !{i32 2, !"darwin.target_variant.triple", !"x86_64-apple-macos10.15"};
 !2 = !{i32 2, !"darwin.target_variant.SDK Version", [2 x i32] [ i32 10, i32 15 ] };
 
 define void @foo() {
diff --git a/llvm/test/MC/MachO/darwin-target-variant.ll b/llvm/test/MC/MachO/darwin-target-variant.ll
index d506ed9..78bd1e9 100644
--- a/llvm/test/MC/MachO/darwin-target-variant.ll
+++ b/llvm/test/MC/MachO/darwin-target-variant.ll
@@ -4,7 +4,7 @@
 target triple = "x86_64-apple-macos10.15";
 !llvm.module.flags = !{!0, !1, !2};
 !0 = !{i32 2, !"SDK Version", [3 x i32] [ i32 10, i32 15, i32 1 ] };
-!1 = !{i32 1, !"darwin.target_variant.triple", !"x86_64-apple-ios13.1-macabi"};
+!1 = !{i32 2, !"darwin.target_variant.triple", !"x86_64-apple-ios13.1-macabi"};
 !2 = !{i32 2, !"darwin.target_variant.SDK Version", [2 x i32] [ i32 13, i32 2 ] };
 
 define void @foo() {