Set storage class of julia globals to dllimport on windows to avoid auto-import weirdness.

Also make the compiler error instead of emitting pseudo-relocations when encountering a reference to a non-exported symbol in a dll.

Co-authored-by: Keno Fischer <keno@juliacomputing.com>
Co-authored-by: Cody Tapscott <84105208+topolarity@users.noreply.github.com>

Author: 3 people

Make.inc

@@ -1365,7 +1365,7 @@ ifeq ($(OS), WINNT)
 HAVE_SSP := 1
 OSLIBS += -Wl,--export-all-symbols -Wl,--version-script=$(BUILDROOT)/src/julia.expmap \
 	$(NO_WHOLE_ARCHIVE) -lpsapi -lkernel32 -lws2_32 -liphlpapi -lwinmm -ldbghelp -luserenv -lsecur32 -latomic
-JLDFLAGS += -Wl,--stack,8388608
+JLDFLAGS += -Wl,--stack,8388608 --disable-auto-import --disable-runtime-pseudo-reloc
 ifeq ($(ARCH),i686)
 JLDFLAGS += -Wl,--large-address-aware
 endif

base/linking.jl

@@ -110,7 +110,7 @@ function ld()
         # LLD supports mingw style linking
         flavor = "gnu"
         m = Sys.ARCH == :x86_64 ? "i386pep" : "i386pe"
-        default_args = `-m $m -Bdynamic --enable-auto-image-base --allow-multiple-definition`
+        default_args = `-m $m -Bdynamic --enable-auto-image-base --allow-multiple-definition --disable-auto-import --disable-runtime-pseudo-reloc`
     elseif Sys.isapple()
         flavor = "darwin"
         arch = Sys.ARCH == :aarch64 ? :arm64 : Sys.ARCH

cli/Makefile

@@ -17,8 +17,7 @@ LOADER_CFLAGS += -DGLIBCXX_LEAST_VERSION_SYMBOL=\"$(shell echo "$(CSL_NEXT_GLIBC
 endif
 
 ifeq ($(OS),WINNT)
-LOADER_LDFLAGS += -municode -mconsole -nostdlib --disable-auto-import \
-                  --disable-runtime-pseudo-reloc -lntdll -lkernel32 -lpsapi
+LOADER_LDFLAGS += -municode -mconsole -nostdlib -lntdll -lkernel32 -lpsapi
 else ifeq ($(OS),Linux)
 LOADER_LDFLAGS += -Wl,--no-as-needed -ldl -lpthread -rdynamic -lc -Wl,--as-needed
 else ifeq ($(OS),FreeBSD)

src/aotcompile.cpp

@@ -1166,6 +1166,8 @@ static void materializePreserved(Module &M, Partition &partition) {
         GV.setInitializer(nullptr);
         GV.setLinkage(GlobalValue::ExternalLinkage);
         GV.setVisibility(GlobalValue::HiddenVisibility);
+        if (GV.getDLLStorageClass() != GlobalValue::DLLStorageClassTypes::DefaultStorageClass)
+            continue; // Don't mess with exported or imported globals
         GV.setDSOLocal(true);
     }
 
@@ -1645,6 +1647,7 @@ void jl_dump_native_impl(void *native_code,
             if (jl_small_typeof_copy) {
                 jl_small_typeof_copy->setVisibility(GlobalValue::HiddenVisibility);
                 jl_small_typeof_copy->setDSOLocal(true);
+                jl_small_typeof_copy->setDLLStorageClass(GlobalValue::DLLStorageClassTypes::DefaultStorageClass);
             }
         }
 
@@ -1673,16 +1676,17 @@ void jl_dump_native_impl(void *native_code,
         // reflect the address of the jl_RTLD_DEFAULT_handle variable
         // back to the caller, so that we can check for consistency issues
         GlobalValue *jlRTLD_DEFAULT_var = jl_emit_RTLD_DEFAULT_var(&metadataM);
-        addComdat(new GlobalVariable(metadataM,
-                                    jlRTLD_DEFAULT_var->getType(),
-                                    true,
-                                    GlobalVariable::ExternalLinkage,
-                                    jlRTLD_DEFAULT_var,
-                                    "jl_RTLD_DEFAULT_handle_pointer"), TheTriple);
-
         Type *T_size = DL.getIntPtrType(Context);
         Type *T_psize = T_size->getPointerTo();
 
+        auto FT = FunctionType::get(Type::getInt8Ty(Context)->getPointerTo()->getPointerTo(), {}, false);
+        auto F = Function::Create(FT, Function::ExternalLinkage, "get_jl_RTLD_DEFAULT_handle_addr", metadataM);
+        llvm::IRBuilder<> builder(BasicBlock::Create(Context, "top", F));
+        builder.CreateRet(jlRTLD_DEFAULT_var);
+        F->setLinkage(GlobalValue::ExternalLinkage);
+        if (TheTriple.isOSBinFormatCOFF())
+            F->setDLLStorageClass(GlobalValue::DLLStorageClassTypes::DLLExportStorageClass);
+        
         if (TheTriple.isOSWindows()) {
             // Windows expect that the function `_DllMainStartup` is present in an dll.
             // Normal compilers use something like Zig's crtdll.c instead we provide a

src/codegen.cpp

@@ -493,9 +493,12 @@ struct JuliaVariable {
         if (GlobalValue *V = m->getNamedValue(name))
             return cast<GlobalVariable>(V);
         auto T_size = m->getDataLayout().getIntPtrType(m->getContext());
-        return new GlobalVariable(*m, _type(T_size),
+        auto var = new GlobalVariable(*m, _type(T_size),
                 isconst, GlobalVariable::ExternalLinkage,
                 NULL, name);
+        if (Triple(m->getTargetTriple()).isOSWindows())
+            var->setDLLStorageClass(GlobalValue::DLLStorageClassTypes::DLLImportStorageClass); // Cross-library imports must be explicit for COFF (Windows)
+        return var;
     }
     GlobalVariable *realize(jl_codectx_t &ctx);
 };
@@ -1786,9 +1789,6 @@ static inline GlobalVariable *prepare_global_in(Module *M, GlobalVariable *G)
                 G->isConstant(), GlobalVariable::ExternalLinkage,
                 nullptr, G->getName(), nullptr, G->getThreadLocalMode());
         proto->copyAttributesFrom(G);
-        // DLLImport only needs to be set for the shadow module
-        // it just gets annoying in the JIT
-        proto->setDLLStorageClass(GlobalValue::DefaultStorageClass);
         return proto;
     }
     return cast<GlobalVariable>(local);

src/staticdata.c

@@ -2838,9 +2838,9 @@ JL_DLLEXPORT void jl_preload_sysimg_so(const char *fname)
 // Allow passing in a module handle directly, rather than a path
 JL_DLLEXPORT void jl_set_sysimg_so(void *handle)
 {
-    void* *jl_RTLD_DEFAULT_handle_pointer;
-    int symbol_found = jl_dlsym(handle, "jl_RTLD_DEFAULT_handle_pointer", (void **)&jl_RTLD_DEFAULT_handle_pointer, 0);
-    if (!symbol_found || (void*)&jl_RTLD_DEFAULT_handle != *jl_RTLD_DEFAULT_handle_pointer)
+    void** (*get_jl_RTLD_DEFAULT_handle_addr)(void) = NULL;
+    int symbol_found = jl_dlsym(handle, "get_jl_RTLD_DEFAULT_handle_addr", (void **)&get_jl_RTLD_DEFAULT_handle_addr, 0);
+    if (!symbol_found || (void*)&jl_RTLD_DEFAULT_handle != (get_jl_RTLD_DEFAULT_handle_addr()))
         jl_error("System image file failed consistency check: maybe opened the wrong version?");
     if (jl_options.cpu_target == NULL)
         jl_options.cpu_target = "native";

sysimage.mk

@@ -16,7 +16,7 @@ $(build_private_libdir)/%.$(SHLIB_EXT): $(build_private_libdir)/%-o.a
 	@$(call PRINT_LINK, $(CXX) $(LDFLAGS) -shared $(fPIC) -L$(build_private_libdir) -L$(build_libdir) -L$(build_shlibdir) -o $@ \
 		$(WHOLE_ARCHIVE) $< $(NO_WHOLE_ARCHIVE) \
 		$(if $(findstring -debug,$(notdir $@)),-ljulia-internal-debug -ljulia-debug,-ljulia-internal -ljulia) \
-		$$([ $(OS) = WINNT ] && echo '' -lssp))
+		$$([ $(OS) = WINNT ] && echo '' -lssp --disable-auto-import --disable-runtime-pseudo-reloc))
 	@$(INSTALL_NAME_CMD)$(notdir $@) $@
 	@$(DSYMUTIL) $@