diff --git a/releasenotes.md b/releasenotes.md
index 9c8bba03b..763d63385 100644
--- a/releasenotes.md
+++ b/releasenotes.md
@@ -5,6 +5,8 @@
 
 ### Changes / improvements
 - Add `--custom-libc` option for custom libc implementations.
+- Remove use of LLVMGetGlobalContext for single module compilation.
+- Fixed bug where constants would get modified when slicing them. #2660
 
 ### Fixes
 - Regression with npot vector in struct triggering an assert #2219.
diff --git a/src/compiler/llvm_codegen.c b/src/compiler/llvm_codegen.c
index 6e4c7e9d9..43ad99d15 100644
--- a/src/compiler/llvm_codegen.c
+++ b/src/compiler/llvm_codegen.c
@@ -1556,7 +1556,7 @@ void **llvm_gen(Module** modules, unsigned module_count)
 	llvm_codegen_setup();
 	if (compiler.build.single_module == SINGLE_MODULE_ON)
 	{
-		LLVMContextRef context = LLVMGetGlobalContext();
+		LLVMContextRef context = LLVMContextCreate();
 		for (int i = 0; i < module_count; i++)
 		{
 			GenContext *result = llvm_gen_module(modules[i], context);
diff --git a/src/compiler/sema_expr.c b/src/compiler/sema_expr.c
index d6c949403..3f514afa4 100644
--- a/src/compiler/sema_expr.c
+++ b/src/compiler/sema_expr.c
@@ -1765,7 +1765,7 @@ INLINE Expr **sema_splat_struct_insert(SemaContext *context, Expr **args, Expr *
 					args[i + index] = expr;
 					break;
 				case CONST_INIT_VALUE:
-					expr = expr_copy(c->init_value);
+					expr = copy_expr_single(c->init_value);
 					break;
 				default:
 					expr = expr_calloc();
@@ -2033,7 +2033,7 @@ INLINE bool sema_call_evaluate_arguments(SemaContext *context, CalledDecl *calle
 				Expr *inner_new = inner;
 				if (type_is_arraylike(inner->type))
 				{
-					inner_new = expr_copy(inner);
+					inner_new = copy_expr_single(inner);
 					if (sema_cast_const(inner_new) && expr_is_const_initializer(inner_new))
 					{
 						ConstInitializer *initializer = inner_new->const_expr.initializer;
@@ -3621,7 +3621,7 @@ static inline bool sema_expr_analyse_typecall(SemaContext *context, Expr *expr)
 		expr_rewrite_const_bool(expr, type_bool, true);
 		return true;
 	}
-	expr_replace(expr, expr_copy(value));
+	expr_replace(expr, copy_expr_single(value));
 	return true;
 NOT_FOUND:
 	if (is_has)
@@ -3726,7 +3726,7 @@ static inline bool sema_call_analyse_member_get(SemaContext *context, Expr *expr
 	// Constant fold the get
 	if (target_kind == TYPE_ENUM && sema_cast_const(inner) && expr_is_const_enum(inner))
 	{
-		expr_replace(expr, expr_copy(inner->const_expr.enum_val->enum_constant.associated[index]));
+		expr_replace(expr, copy_expr_single(inner->const_expr.enum_val->enum_constant.associated[index]));
 		return true;
 	}
 	expr->expr_kind = target_kind == TYPE_BITSTRUCT ? EXPR_BITACCESS : EXPR_ACCESS_RESOLVED;
@@ -6270,7 +6270,7 @@ static inline void sema_expr_flatten_const_ident(Expr *expr)
 	sema_expr_flatten_const_ident(init_expr);
 	if (expr_is_const(init_expr))
 	{
-		expr_replace(expr, expr_copy(init_expr));
+		expr_replace(expr, copy_expr_single(init_expr));
 	}
 }
 
diff --git a/src/compiler/sema_initializers.c b/src/compiler/sema_initializers.c
index fd5df5d36..3736bc42b 100644
--- a/src/compiler/sema_initializers.c
+++ b/src/compiler/sema_initializers.c
@@ -951,7 +951,7 @@ void const_init_rewrite_to_value(ConstInitializer *const_init, Expr *value)
 		Decl *ident = decl_flatten(value->ident_expr);
 		ASSERT(ident->decl_kind == DECL_VAR);
 		ASSERT(ident->var.kind == VARDECL_CONST);
-		const_init_rewrite_to_value(const_init, expr_copy(ident->var.init_expr));
+		const_init_rewrite_to_value(const_init, copy_expr_single(ident->var.init_expr));
 		return;
 	}
 	const_init->init_value = value;
diff --git a/test/test_suite/arrays/slice_constant_mod.c3t b/test/test_suite/arrays/slice_constant_mod.c3t
new file mode 100644
index 000000000..fc26a0c2a
--- /dev/null
+++ b/test/test_suite/arrays/slice_constant_mod.c3t
@@ -0,0 +1,27 @@
+module my_module { GENNY };
+import std::io;
+
+const uint[5] H = { 1, 2, 3, 4, 5 };
+
+macro void get(String to_print)
+{
+    uint[3] slice_thing;
+    io::printfn(to_print, GENNY);
+    $if GENNY != 1:
+        io::printn("not");
+    $else
+        // !< PROBLEM LINES >!
+        slice_thing[:1] = H[:1];
+        slice_thing[1:2] = H[3:2];
+        // ===================
+        io::printn("is!");
+    $endif
+}
+
+module testing_branch;
+import my_module;
+
+fn void main()
+{
+    my_module::get{1}("The %d string");
+}
\ No newline at end of file
diff --git a/test/test_suite/slices/various_const_slicing.c3t b/test/test_suite/slices/various_const_slicing.c3t
index 090d1c1ff..d3d7a1975 100644
--- a/test/test_suite/slices/various_const_slicing.c3t
+++ b/test/test_suite/slices/various_const_slicing.c3t
@@ -33,7 +33,8 @@ fn int main()
 
 /* #expect: test.ll
 
-@test.FOO = local_unnamed_addr constant [2 x i32] [i32 2, i32 3], align 16
+
+@test.FOO = local_unnamed_addr constant [4 x i32] [i32 1, i32 2, i32 3, i32 4], align 16
 @.__const_slice = private unnamed_addr global [2 x i32] [i32 2, i32 3], align 4
 @test.y2 = local_unnamed_addr global %"int[]" { ptr @.__const_slice, i64 2 }, align 8
 @.__const = private unnamed_addr constant [1 x i32] [i32 1], align 4
@@ -299,24 +300,31 @@ assign_optional71:                                ; preds = %noerr_block68
   br label %guard_block73
 after_check72:                                    ; preds = %noerr_block68
   br label %noerr_block74
+
 guard_block73:                                    ; preds = %assign_optional71
   br label %voiderr82
+
 noerr_block74:                                    ; preds = %after_check72
   %47 = call i64 @std.io.File.flush(ptr %36)
   %not_err76 = icmp eq i64 %47, 0
   %48 = call i1 @llvm.expect.i1(i1 %not_err76, i1 true)
   br i1 %48, label %after_check78, label %assign_optional77
+
 assign_optional77:                                ; preds = %noerr_block74
   store i64 %47, ptr %error_var75, align 8
   br label %guard_block79
+
 after_check78:                                    ; preds = %noerr_block74
   br label %noerr_block80
+
 guard_block79:                                    ; preds = %assign_optional77
   br label %voiderr82
+
 noerr_block80:                                    ; preds = %after_check78
   %49 = load i64, ptr %len52, align 8
   %add81 = add i64 %49, 1
   br label %voiderr82
+
 voiderr82:                                        ; preds = %noerr_block80, %guard_block79, %guard_block73, %guard_block67
   call void @llvm.memcpy.p0.p0.i32(ptr align 4 %literal83, ptr align 4 @.__const.6, i32 12, i1 false)
   %50 = insertvalue %"int[]" undef, ptr %literal83, 0
@@ -339,13 +347,17 @@ voiderr82:                                        ; preds = %noerr_block80, %gua
   %not_err96 = icmp eq i64 %58, 0
   %59 = call i1 @llvm.expect.i1(i1 %not_err96, i1 true)
   br i1 %59, label %after_check98, label %assign_optional97
+
 assign_optional97:                                ; preds = %voiderr82
   store i64 %58, ptr %error_var85, align 8
   br label %guard_block99
+
 after_check98:                                    ; preds = %voiderr82
   br label %noerr_block100
+
 guard_block99:                                    ; preds = %assign_optional97
   br label %voiderr114
+
 noerr_block100:                                   ; preds = %after_check98
   %60 = load i64, ptr %retparam90, align 8
   store i64 %60, ptr %len84, align 8
@@ -353,29 +365,38 @@ noerr_block100:                                   ; preds = %after_check98
   %not_err102 = icmp eq i64 %61, 0
   %62 = call i1 @llvm.expect.i1(i1 %not_err102, i1 true)
   br i1 %62, label %after_check104, label %assign_optional103
+
 assign_optional103:                               ; preds = %noerr_block100
   store i64 %61, ptr %error_var101, align 8
   br label %guard_block105
+
 after_check104:                                   ; preds = %noerr_block100
   br label %noerr_block106
+
 guard_block105:                                   ; preds = %assign_optional103
   br label %voiderr114
+
 noerr_block106:                                   ; preds = %after_check104
   %63 = call i64 @std.io.File.flush(ptr %52)
   %not_err108 = icmp eq i64 %63, 0
   %64 = call i1 @llvm.expect.i1(i1 %not_err108, i1 true)
   br i1 %64, label %after_check110, label %assign_optional109
+
 assign_optional109:                               ; preds = %noerr_block106
   store i64 %63, ptr %error_var107, align 8
   br label %guard_block111
+
 after_check110:                                   ; preds = %noerr_block106
   br label %noerr_block112
+
 guard_block111:                                   ; preds = %assign_optional109
   br label %voiderr114
+
 noerr_block112:                                   ; preds = %after_check110
   %65 = load i64, ptr %len84, align 8
   %add113 = add i64 %65, 1
   br label %voiderr114
+
 voiderr114:                                       ; preds = %noerr_block112, %guard_block111, %guard_block105, %guard_block99
   call void @llvm.memcpy.p0.p0.i32(ptr align 4 %literal115, ptr align 4 @.__const.8, i32 8, i1 false)
   call void @llvm.memcpy.p0.p0.i32(ptr align 4 %x116, ptr align 4 %literal115, i32 8, i1 false)
@@ -398,13 +419,17 @@ voiderr114:                                       ; preds = %noerr_block112, %gu
   %not_err130 = icmp eq i64 %72, 0
   %73 = call i1 @llvm.expect.i1(i1 %not_err130, i1 true)
   br i1 %73, label %after_check132, label %assign_optional131
+
 assign_optional131:                               ; preds = %voiderr114
   store i64 %72, ptr %error_var119, align 8
   br label %guard_block133
+
 after_check132:                                   ; preds = %voiderr114
   br label %noerr_block134
+
 guard_block133:                                   ; preds = %assign_optional131
   br label %voiderr148
+
 noerr_block134:                                   ; preds = %after_check132
   %74 = load i64, ptr %retparam124, align 8
   store i64 %74, ptr %len118, align 8
@@ -412,29 +437,38 @@ noerr_block134:                                   ; preds = %after_check132
   %not_err136 = icmp eq i64 %75, 0
   %76 = call i1 @llvm.expect.i1(i1 %not_err136, i1 true)
   br i1 %76, label %after_check138, label %assign_optional137
+
 assign_optional137:                               ; preds = %noerr_block134
   store i64 %75, ptr %error_var135, align 8
   br label %guard_block139
+
 after_check138:                                   ; preds = %noerr_block134
   br label %noerr_block140
+
 guard_block139:                                   ; preds = %assign_optional137
   br label %voiderr148
+
 noerr_block140:                                   ; preds = %after_check138
   %77 = call i64 @std.io.File.flush(ptr %66)
   %not_err142 = icmp eq i64 %77, 0
   %78 = call i1 @llvm.expect.i1(i1 %not_err142, i1 true)
   br i1 %78, label %after_check144, label %assign_optional143
+
 assign_optional143:                               ; preds = %noerr_block140
   store i64 %77, ptr %error_var141, align 8
   br label %guard_block145
+
 after_check144:                                   ; preds = %noerr_block140
   br label %noerr_block146
+
 guard_block145:                                   ; preds = %assign_optional143
   br label %voiderr148
+
 noerr_block146:                                   ; preds = %after_check144
   %79 = load i64, ptr %len118, align 8
   %add147 = add i64 %79, 1
   br label %voiderr148
+
 voiderr148:                                       ; preds = %noerr_block146, %guard_block145, %guard_block139, %guard_block133
   %80 = call ptr @std.io.stdout()
   %81 = insertvalue %any undef, ptr %80, 0
@@ -454,13 +488,17 @@ voiderr148:                                       ; preds = %noerr_block146, %gu
   %not_err161 = icmp eq i64 %86, 0
   %87 = call i1 @llvm.expect.i1(i1 %not_err161, i1 true)
   br i1 %87, label %after_check163, label %assign_optional162
+
 assign_optional162:                               ; preds = %voiderr148
   store i64 %86, ptr %error_var150, align 8
   br label %guard_block164
+
 after_check163:                                   ; preds = %voiderr148
   br label %noerr_block165
+
 guard_block164:                                   ; preds = %assign_optional162
   br label %voiderr179
+
 noerr_block165:                                   ; preds = %after_check163
   %88 = load i64, ptr %retparam155, align 8
   store i64 %88, ptr %len149, align 8
@@ -468,29 +506,38 @@ noerr_block165:                                   ; preds = %after_check163
   %not_err167 = icmp eq i64 %89, 0
   %90 = call i1 @llvm.expect.i1(i1 %not_err167, i1 true)
   br i1 %90, label %after_check169, label %assign_optional168
+
 assign_optional168:                               ; preds = %noerr_block165
   store i64 %89, ptr %error_var166, align 8
   br label %guard_block170
+
 after_check169:                                   ; preds = %noerr_block165
   br label %noerr_block171
+
 guard_block170:                                   ; preds = %assign_optional168
   br label %voiderr179
+
 noerr_block171:                                   ; preds = %after_check169
   %91 = call i64 @std.io.File.flush(ptr %80)
   %not_err173 = icmp eq i64 %91, 0
   %92 = call i1 @llvm.expect.i1(i1 %not_err173, i1 true)
   br i1 %92, label %after_check175, label %assign_optional174
+
 assign_optional174:                               ; preds = %noerr_block171
   store i64 %91, ptr %error_var172, align 8
   br label %guard_block176
+
 after_check175:                                   ; preds = %noerr_block171
   br label %noerr_block177
+
 guard_block176:                                   ; preds = %assign_optional174
   br label %voiderr179
+
 noerr_block177:                                   ; preds = %after_check175
   %93 = load i64, ptr %len149, align 8
   %add178 = add i64 %93, 1
   br label %voiderr179
+
 voiderr179:                                       ; preds = %noerr_block177, %guard_block176, %guard_block170, %guard_block164
   ret i32 0
 }