diff --git a/src/codegen/enums.rs b/src/codegen/enums.rs
index 63bf8bb8c..810acbe0d 100644
--- a/src/codegen/enums.rs
+++ b/src/codegen/enums.rs
@@ -481,7 +481,7 @@ impl FromGlib<{sys_crate_name}::{ffi_name}> for {name} {{
 
     #[inline]
     unsafe fn from_value(value: &'a {gvalue}) -> Self {{
-        {assert}from_glib({glib}(value.to_glib_none().0))
+        {assert}unsafe {{ from_glib({glib}(value.to_glib_none().0)) }}
     }}
 }}",
             name = enum_.name,
diff --git a/src/codegen/flags.rs b/src/codegen/flags.rs
index d7502bc51..83afeed9e 100644
--- a/src/codegen/flags.rs
+++ b/src/codegen/flags.rs
@@ -319,7 +319,7 @@ impl FromGlib<{sys_crate_name}::{ffi_name}> for {name} {{
 
     #[inline]
     unsafe fn from_value(value: &'a {gvalue}) -> Self {{
-        {assert}from_glib({glib}(value.to_glib_none().0))
+        {assert}unsafe {{ from_glib({glib}(value.to_glib_none().0)) }}
     }}
 }}",
             name = flags.name,
diff --git a/src/codegen/function.rs b/src/codegen/function.rs
index f0195a68b..d499eeaa5 100644
--- a/src/codegen/function.rs
+++ b/src/codegen/function.rs
@@ -92,7 +92,7 @@ pub fn generate(
 
     let unsafe_ = if analysis.unsafe_ { "unsafe " } else { "" };
     let declaration = declaration(env, analysis);
-    let suffix = if only_declaration { ";" } else { " {" };
+    let suffix = if only_declaration { ";" } else if analysis.unsafe_ { " { unsafe {" } else { " {" };
 
     writeln!(w)?;
     cfg_deprecated(w, env, None, analysis.deprecated_version, commented, indent)?;
@@ -187,7 +187,11 @@ pub fn generate(
                     writeln!(w)?;
                 }
             }
-            writeln!(w, "{}{}}}", tabs(indent), comment_prefix)?;
+            if analysis.unsafe_ {
+                writeln!(w, "{}{}}}}}", tabs(indent), comment_prefix)?;
+            } else {
+                writeln!(w, "{}{}}}", tabs(indent), comment_prefix)?;
+            }
         }
     }
 
diff --git a/src/codegen/function_body_chunk.rs b/src/codegen/function_body_chunk.rs
index 6bee059c9..97bf6a9c5 100644
--- a/src/codegen/function_body_chunk.rs
+++ b/src/codegen/function_body_chunk.rs
@@ -554,11 +554,11 @@ impl Builder {
                 is_mut: false,
                 value: Box::new(Chunk::Custom(
                     if is_destroy || trampoline.scope.is_async() {
-                        format!("Box_::from_raw({} as *mut {})", func, trampoline.bound_name)
+                        format!("unsafe {{ Box_::from_raw({} as *mut {}) }}", func, trampoline.bound_name)
                     } else if trampoline.scope.is_call() {
                         format!("{} as *mut {}", func, trampoline.bound_name)
                     } else {
-                        format!("&*({} as *mut {})", func, trampoline.bound_name)
+                        format!("unsafe {{ &*({} as *mut {}) }}", func, trampoline.bound_name)
                     },
                 )),
                 type_: None,
diff --git a/src/codegen/general.rs b/src/codegen/general.rs
index 967fb4cbc..282c75b43 100644
--- a/src/codegen/general.rs
+++ b/src/codegen/general.rs
@@ -401,10 +401,10 @@ fn define_boxed_type_internal(
     };
     writeln!(
         w,
-        "\t\tcopy => |ptr| {}::{}({}),",
+        "\t\tcopy => |ptr| unsafe {{ {}::{}({}) }},",
         sys_crate_name, copy_fn.glib_name, mut_ov
     )?;
-    writeln!(w, "\t\tfree => |ptr| {sys_crate_name}::{free_fn}(ptr),")?;
+    writeln!(w, "\t\tfree => |ptr| unsafe {{ {sys_crate_name}::{free_fn}(ptr) }},")?;
 
     if let (
         Some(init_function_expression),
@@ -613,8 +613,8 @@ fn define_shared_type_internal(
     )?;
     writeln!(w)?;
     writeln!(w, "\tmatch fn {{")?;
-    writeln!(w, "\t\tref => |ptr| {sys_crate_name}::{ref_fn}(ptr),")?;
-    writeln!(w, "\t\tunref => |ptr| {sys_crate_name}::{unref_fn}(ptr),")?;
+    writeln!(w, "\t\tref => |ptr| unsafe {{ {sys_crate_name}::{ref_fn}(ptr) }},")?;
+    writeln!(w, "\t\tunref => |ptr| unsafe {{ {sys_crate_name}::{unref_fn}(ptr) }},")?;
     if let Some(get_type_fn) = get_type_fn {
         writeln!(w, "\t\ttype_ => || {sys_crate_name}::{get_type_fn}(),")?;
     }
diff --git a/src/codegen/sys/lib_.rs b/src/codegen/sys/lib_.rs
index abc97414d..031d2f02b 100644
--- a/src/codegen/sys/lib_.rs
+++ b/src/codegen/sys/lib_.rs
@@ -77,7 +77,7 @@ fn generate_lib(w: &mut dyn Write, env: &Env) -> Result<()> {
     }
 
     if !env.namespaces.main().shared_libs.is_empty() {
-        writeln!(w, "extern \"C\" {{")?;
+        writeln!(w, "unsafe extern \"C\" {{")?;
         functions::generate_enums_funcs(w, env, &enums)?;
         functions::generate_bitfields_funcs(w, env, &bitfields)?;
         functions::generate_unions_funcs(w, env, &unions)?;
diff --git a/src/codegen/trampoline.rs b/src/codegen/trampoline.rs
index b339ef074..029b607d5 100644
--- a/src/codegen/trampoline.rs
+++ b/src/codegen/trampoline.rs
@@ -45,7 +45,7 @@ pub fn generate(
 
     writeln!(
         w,
-        "{}unsafe extern \"C\" fn {}<{}F: {}>({}, f: {}){} {{",
+        "{}unsafe extern \"C\" fn {}<{}F: {}>({}, f: {}){} {{ unsafe {{",
         prepend,
         analysis.name,
         self_bound,
@@ -58,7 +58,7 @@ pub fn generate(
     transformation_vars(w, env, analysis, &prepend)?;
     let call = trampoline_call_func(env, analysis, in_trait);
     writeln!(w, "{prepend}\t{call}")?;
-    writeln!(w, "{prepend}}}")?;
+    writeln!(w, "{prepend}}}}}")?;
 
     Ok(())
 }