Use weak on dyn-symbols on Linux.

tsoding · Dec 27, 2024 · 08e8c9b · 08e8c9b
1 parent 6251524
commit 08e8c9b
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Showing 6 changed files with 9 additions and 8 deletions.
diff --git a/releasenotes.md b/releasenotes.md
@@ -26,6 +26,7 @@
 - Prevent DString from being initialized with "".
 - Fix bug in OnStackAllocator when freeing overallocated data. #1720
 - Use `weak_odr` rather than `weak` on Windows which seems to prevent issues such as #1704.
+- Use `weak` on dyn-symbols on Linux.
 
 ### Stdlib changes
 - Increase BitWriter.write_bits limit up to 32 bits.

diff --git a/src/compiler/llvm_codegen.c b/src/compiler/llvm_codegen.c
@@ -468,7 +468,7 @@ void llvm_set_global_tls(Decl *decl)
 	}
 }
 
-static void llvm_set_weak(GenContext *c, LLVMValueRef global)
+void llvm_set_weak(GenContext *c, LLVMValueRef global)
 {
 	LLVMSetLinkage(global, compiler.platform.os == OS_TYPE_WIN32 ? LLVMWeakODRLinkage : LLVMWeakAnyLinkage);
 	LLVMSetVisibility(global, LLVMDefaultVisibility);

diff --git a/src/compiler/llvm_codegen_function.c b/src/compiler/llvm_codegen_function.c
@@ -418,7 +418,7 @@ void llvm_emit_function_body(GenContext *c, Decl *decl)
 		scratch_buffer_append(".__c3_atexit_");
 		scratch_buffer_set_extern_decl_name(decl, false);
 		LLVMValueRef func = LLVMAddFunction(c->module, scratch_buffer_to_string(), c->xtor_func_type);
-
+		llvm_set_weak(c, func);
 		LLVMBuilderRef builder = llvm_create_function_entry(c, func, NULL);
 		LLVMValueRef args[1] = { decl->backend_ref };
 		LLVMBuildCall2(builder, c->atexit_type, atexit, args, 1, "");
@@ -598,6 +598,7 @@ void llvm_emit_dynamic_functions(GenContext *c, Decl **funcs)
 		scratch_buffer_append("$ct.dyn.");
 		scratch_buffer_set_extern_decl_name(decl, false);
 		LLVMValueRef global = llvm_add_global_raw(c, scratch_buffer_copy(), c->dtable_type, 0);
+		llvm_set_weak(c, global);
 		Decl *proto = declptrzero(decl->func_decl.interface_method);
 		LLVMValueRef proto_ref = proto ? llvm_get_ref(c, proto) : llvm_get_selector(c, decl->name);
 

diff --git a/src/compiler/llvm_codegen_internal.h b/src/compiler/llvm_codegen_internal.h
@@ -371,6 +371,7 @@ void llvm_set_linkonce(GenContext *c, LLVMValueRef global);
 void llvm_set_comdat(GenContext *c, LLVMValueRef global);
 void llvm_set_private_declaration(LLVMValueRef alloc);
 void llvm_set_decl_linkage(GenContext *c, Decl *decl);
+void llvm_set_weak(GenContext *c, LLVMValueRef global);
 
 void llvm_set_internal_linkage(LLVMValueRef alloc);
 void llvm_set_global_tls(Decl *decl);

diff --git a/test/test_suite/dynamic/inherit_linux.c3t b/test/test_suite/dynamic/inherit_linux.c3t
@@ -50,8 +50,8 @@ $"$sel.hello" = comdat any
 @.panic_msg = internal constant [42 x i8] c"No method 'tesT' could be found on target\00", align 1
 @.func = internal constant [5 x i8] c"main\00", align 1
 @std.core.builtin.panic = extern_weak global ptr, align 8
-@"$ct.dyn.inherit.Test.tesT" = global { ptr, ptr, ptr } { ptr @inherit.Test.tesT, ptr @"$sel.tesT", ptr inttoptr (i64 -1 to ptr) }, align 8
-@"$ct.dyn.inherit.Test.hello" = global { ptr, ptr, ptr } { ptr @inherit.Test.hello, ptr @"$sel.hello", ptr inttoptr (i64 -1 to ptr) }, align 8
+@"$ct.dyn.inherit.Test.tesT" = weak global { ptr, ptr, ptr } { ptr @inherit.Test.tesT, ptr @"$sel.tesT", ptr inttoptr (i64 -1 to ptr) }, comdat, align 8
+@"$ct.dyn.inherit.Test.hello" = weak global { ptr, ptr, ptr } { ptr @inherit.Test.hello, ptr @"$sel.hello", ptr inttoptr (i64 -1 to ptr) }, comdat, align 8
 @"$sel.hello" = linkonce_odr constant [6 x i8] c"hello\00", comdat, align 1
 @llvm.global_ctors = appending global [1 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 1, ptr @.c3_dynamic_register, ptr null }]
 define void @inherit.Test.tesT(ptr %0) #0 {

diff --git a/test/test_suite/dynamic/overlapping_function_linux.c3t b/test/test_suite/dynamic/overlapping_function_linux.c3t
@@ -41,8 +41,8 @@ fn void main()
 @.file = internal constant [30 x i8] c"overlapping_function_linux.c3\00", align 1
 @.func = internal constant [5 x i8] c"main\00", align 1
 @std.core.builtin.panic = extern_weak global ptr, align 8
-@"$ct.dyn.overlap.Test.tesT" = global { ptr, ptr, ptr } { ptr @overlap.Test.tesT, ptr @"$sel.tesT", ptr inttoptr (i64 -1 to ptr) }, align 8
-@"$ct.dyn.overlap.Test.foo" = global { ptr, ptr, ptr } { ptr @overlap.Test.foo, ptr @"$sel.foo", ptr inttoptr (i64 -1 to ptr) }, align 8
+@"$ct.dyn.overlap.Test.tesT" = weak global { ptr, ptr, ptr } { ptr @overlap.Test.tesT, ptr @"$sel.tesT", ptr inttoptr (i64 -1 to ptr) }, comdat, align 8
+@"$ct.dyn.overlap.Test.foo" = weak global { ptr, ptr, ptr } { ptr @overlap.Test.foo, ptr @"$sel.foo", ptr inttoptr (i64 -1 to ptr) }, comdat, align 8
 @"$sel.foo" = linkonce_odr constant [4 x i8] c"foo\00", comdat, align 1
 @llvm.global_ctors = appending global [1 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 1, ptr @.c3_dynamic_register, ptr null }]
 ; Function Attrs: nounwind uwtable
@@ -134,8 +134,6 @@ entry:
   call void @overlap.main()
   ret i32 0
 }
-
-
 define weak ptr @.dyn_search(ptr %0, ptr %1) unnamed_addr comdat {
 entry:
   br label %check