Revert "Support taking extern pointers at comptime"

This reverts commit d3ebd428650748e60db70dd2171cc044855814b1.

This caused a build failure on multiple targets.

1 files changed, 20 insertions, 50 deletions

diff --git a/src/codegen.cpp b/src/codegen.cpp
index 246ecb4369..3f3d80d51d 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -7754,13 +7754,6 @@ static LLVMValueRef gen_const_val(CodeGen *g, ZigValue *const_val, const char *n
 }
 
 static void render_const_val(CodeGen *g, ZigValue *const_val, const char *name) {
-    if (const_val->special == ConstValSpecialRuntime) {
-        // `const_val` refers to an extern variable. Don't generate an `LLVMValueRef` for
-        // the variable. We shouldn't call `LLVMSetInitializer` on it either.
-        assert(const_val->llvm_global);
-        return;
-    }
-
     if (!const_val->llvm_value)
         const_val->llvm_value = gen_const_val(g, const_val, name);
 
@@ -7769,13 +7762,6 @@ static void render_const_val(CodeGen *g, ZigValue *const_val, const char *name)
 }
 
 static void render_const_val_global(CodeGen *g, ZigValue *const_val, const char *name) {
-    if (const_val->special == ConstValSpecialRuntime) {
-        // `const_val` refers to an extern variable. `llvm_global` should already
-        // have been created by an earlier codegen pass.
-        assert(const_val->llvm_global);
-        return;
-    }
-
     if (!const_val->llvm_global) {
         LLVMTypeRef type_ref = const_val->llvm_value ?
             LLVMTypeOf(const_val->llvm_value) : get_llvm_type(g, const_val->type);
@@ -7905,39 +7891,6 @@ static void do_code_gen(CodeGen *g) {
 
     generate_error_name_table(g);
 
-    // Create extern variables
-    for (size_t i = 0; i < g->global_vars.length; i += 1) {
-        TldVar *tld_var = g->global_vars.at(i);
-        ZigVar *var = tld_var->var;
-
-        bool externally_initialized = var->decl_node->data.variable_declaration.expr == nullptr;
-        if (!externally_initialized) {
-            continue;
-        }
-
-        assert(var->decl_node->data.variable_declaration.is_extern);
-        const char *symbol_name = var->name;
-
-        LLVMValueRef global_value;
-        LLVMValueRef existing_llvm_var = LLVMGetNamedGlobal(g->module, symbol_name);
-        if (existing_llvm_var) {
-            global_value = LLVMConstBitCast(existing_llvm_var,
-                    LLVMPointerType(get_llvm_type(g, var->var_type), 0));
-        } else {
-            global_value = LLVMAddGlobal(g->module, get_llvm_type(g, var->var_type), symbol_name);
-            // TODO debug info for the extern variable
-
-            LLVMSetLinkage(global_value, LLVMExternalLinkage);
-            maybe_import_dll(g, global_value, GlobalLinkageIdStrong);
-            LLVMSetAlignment(global_value, var->align_bytes);
-            LLVMSetGlobalConstant(global_value, var->gen_is_const);
-            set_global_tls(g, var, global_value);
-        }
-
-        var->value_ref = global_value;
-        var->const_value->llvm_global = global_value;
-    }
-
     // Generate module level variables
     for (size_t i = 0; i < g->global_vars.length; i += 1) {
         TldVar *tld_var = g->global_vars.at(i);
@@ -8003,12 +7956,28 @@ static void do_code_gen(CodeGen *g) {
             linkage = global_export->linkage;
         }
 
+        LLVMValueRef global_value;
         bool externally_initialized = var->decl_node->data.variable_declaration.expr == nullptr;
-        if (!externally_initialized) {
+        if (externally_initialized) {
+            LLVMValueRef existing_llvm_var = LLVMGetNamedGlobal(g->module, symbol_name);
+            if (existing_llvm_var) {
+                global_value = LLVMConstBitCast(existing_llvm_var,
+                        LLVMPointerType(get_llvm_type(g, var->var_type), 0));
+            } else {
+                global_value = LLVMAddGlobal(g->module, get_llvm_type(g, var->var_type), symbol_name);
+                // TODO debug info for the extern variable
+
+                LLVMSetLinkage(global_value, to_llvm_linkage(linkage));
+                maybe_import_dll(g, global_value, GlobalLinkageIdStrong);
+                LLVMSetAlignment(global_value, var->align_bytes);
+                LLVMSetGlobalConstant(global_value, var->gen_is_const);
+                set_global_tls(g, var, global_value);
+            }
+        } else {
             bool exported = (linkage != GlobalLinkageIdInternal);
             render_const_val(g, var->const_value, symbol_name);
             render_const_val_global(g, var->const_value, symbol_name);
-            LLVMValueRef global_value = var->const_value->llvm_global;
+            global_value = var->const_value->llvm_global;
 
             if (exported) {
                 LLVMSetLinkage(global_value, to_llvm_linkage(linkage));
@@ -8028,9 +7997,10 @@ static void do_code_gen(CodeGen *g) {
 
             LLVMSetGlobalConstant(global_value, var->gen_is_const);
             set_global_tls(g, var, global_value);
-            var->value_ref = global_value;
         }
 
+        var->value_ref = global_value;
+
         for (size_t export_i = 1; export_i < var->export_list.length; export_i += 1) {
             GlobalExport *global_export = &var->export_list.items[export_i];
             LLVMAddAlias(g->module, LLVMTypeOf(var->value_ref), var->value_ref, buf_ptr(&global_export->name));