rust/rust-pr91070.patch

95 lines
3.1 KiB
Diff

diff --git a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
index e77d29bed712..f3d8eb2602a3 100644
--- a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
@@ -124,8 +124,18 @@ extern "C" LLVMValueRef LLVMRustGetOrInsertFunction(LLVMModuleRef M,
extern "C" LLVMValueRef
LLVMRustGetOrInsertGlobal(LLVMModuleRef M, const char *Name, size_t NameLen, LLVMTypeRef Ty) {
+ Module *Mod = unwrap(M);
StringRef NameRef(Name, NameLen);
- return wrap(unwrap(M)->getOrInsertGlobal(NameRef, unwrap(Ty)));
+
+ // We don't use Module::getOrInsertGlobal because that returns a Constant*,
+ // which may either be the real GlobalVariable*, or a constant bitcast of it
+ // if our type doesn't match the original declaration. We always want the
+ // GlobalVariable* so we can access linkage, visibility, etc.
+ GlobalVariable *GV = Mod->getGlobalVariable(NameRef, true);
+ if (!GV)
+ GV = new GlobalVariable(*Mod, unwrap(Ty), false,
+ GlobalValue::ExternalLinkage, nullptr, NameRef);
+ return wrap(GV);
}
extern "C" LLVMValueRef
diff --git a/src/test/ui/statics/issue-91050-1.rs b/src/test/ui/statics/issue-91050-1.rs
new file mode 100644
index 000000000000..403a41462ef1
--- /dev/null
+++ b/src/test/ui/statics/issue-91050-1.rs
@@ -0,0 +1,34 @@
+// build-pass
+// compile-flags: --crate-type=rlib --emit=llvm-ir -Cno-prepopulate-passes
+
+// This test declares globals by the same name with different types, which
+// caused problems because Module::getOrInsertGlobal would return a Constant*
+// bitcast instead of a GlobalVariable* that could access linkage/visibility.
+// In alt builds with LLVM assertions this would fail:
+//
+// rustc: /checkout/src/llvm-project/llvm/include/llvm/Support/Casting.h:269:
+// typename cast_retty<X, Y *>::ret_type llvm::cast(Y *) [X = llvm::GlobalValue, Y = llvm::Value]:
+// Assertion `isa<X>(Val) && "cast<Ty>() argument of incompatible type!"' failed.
+//
+// In regular builds, the bad cast was UB, like "Invalid LLVMRustVisibility value!"
+
+pub mod before {
+ #[no_mangle]
+ pub static GLOBAL1: [u8; 1] = [1];
+}
+
+pub mod inner {
+ extern "C" {
+ pub static GLOBAL1: u8;
+ pub static GLOBAL2: u8;
+ }
+
+ pub fn call() {
+ drop(unsafe { (GLOBAL1, GLOBAL2) });
+ }
+}
+
+pub mod after {
+ #[no_mangle]
+ pub static GLOBAL2: [u8; 1] = [2];
+}
diff --git a/src/test/ui/statics/issue-91050-2.rs b/src/test/ui/statics/issue-91050-2.rs
new file mode 100644
index 000000000000..2ff954d15cab
--- /dev/null
+++ b/src/test/ui/statics/issue-91050-2.rs
@@ -0,0 +1,24 @@
+// build-pass
+// compile-flags: --crate-type=rlib --emit=llvm-ir -Cno-prepopulate-passes
+
+// This is a variant of issue-91050-1.rs -- see there for an explanation.
+
+pub mod before {
+ extern "C" {
+ pub static GLOBAL1: [u8; 1];
+ }
+
+ pub unsafe fn do_something_with_array() -> u8 {
+ GLOBAL1[0]
+ }
+}
+
+pub mod inner {
+ extern "C" {
+ pub static GLOBAL1: u8;
+ }
+
+ pub unsafe fn call() -> u8 {
+ GLOBAL1 + 42
+ }
+}