Drop 'static for pub const strings for rustc>1.17

Constant and static declaration have a 'static live time by default,
that is already elided since 1.17.

Clippy complains on this kind of strings that are present in the
generated code.

This patch remove the 'static live time for those strings when rustc >
1.17 via a new added RustFeature.

Fix #1612

Signed-off-by: Alberto Planas <aplanas@suse.com>

9 files changed, 57 insertions, 14 deletions

diff --git a/src/codegen/mod.rs b/src/codegen/mod.rs
index b703a106..19886e3d 100644
--- a/src/codegen/mod.rs
+++ b/src/codegen/mod.rs
@@ -665,10 +665,21 @@ impl CodeGenerator for Var {
                     match String::from_utf8(bytes.clone()) {
                         Ok(string) => {
                             let cstr = helpers::ast_ty::cstr_expr(string);
-                            result.push(quote! {
-                                #(#attrs)*
-                                pub const #canonical_ident : &'static #ty = #cstr ;
-                            });
+                            if ctx
+                                .options()
+                                .rust_features
+                                .static_lifetime_elision
+                            {
+                                result.push(quote! {
+                                    #(#attrs)*
+                                    pub const #canonical_ident : &#ty = #cstr ;
+                                });
+                            } else {
+                                result.push(quote! {
+                                    #(#attrs)*
+                                    pub const #canonical_ident : &'static #ty = #cstr ;
+                                });
+                            }
                         }
                         Err(..) => {
                             let bytes = helpers::ast_ty::byte_array_expr(bytes);
diff --git a/src/features.rs b/src/features.rs
index 99b789e0..a786f07f 100644
--- a/src/features.rs
+++ b/src/features.rs
@@ -87,8 +87,9 @@ macro_rules! rust_target_base {
         $x_macro!(
             /// Rust stable 1.0
             => Stable_1_0 => 1.0;
-            /// Rust stable 1.1
-            => Stable_1_1 => 1.1;
+            /// Rust stable 1.17
+            ///  * Static lifetime elision ([RFC 1623](https://github.com/rust-lang/rfcs/blob/master/text/1623-static.md))
+            => Stable_1_17 => 1.17;
             /// Rust stable 1.19
             ///  * Untagged unions ([RFC 1444](https://github.com/rust-lang/rfcs/blob/master/text/1444-union.md))
             => Stable_1_19 => 1.19;
@@ -191,6 +192,9 @@ macro_rules! rust_feature_def {
 // documentation for the relevant variant in the rust_target_base macro
 // definition.
 rust_feature_def!(
+    Stable_1_17 {
+        => static_lifetime_elision;
+    }
     Stable_1_19 {
         => untagged_union;
     }
@@ -249,7 +253,8 @@ mod test {
     fn target_features() {
         let f_1_0 = RustFeatures::from(RustTarget::Stable_1_0);
         assert!(
-            !f_1_0.core_ffi_c_void &&
+            !f_1_0.static_lifetime_elision &&
+                !f_1_0.core_ffi_c_void &&
                 !f_1_0.untagged_union &&
                 !f_1_0.associated_const &&
                 !f_1_0.builtin_clone_impls &&
@@ -258,7 +263,8 @@ mod test {
         );
         let f_1_21 = RustFeatures::from(RustTarget::Stable_1_21);
         assert!(
-            !f_1_21.core_ffi_c_void &&
+            f_1_21.static_lifetime_elision &&
+                !f_1_21.core_ffi_c_void &&
                 f_1_21.untagged_union &&
                 f_1_21.associated_const &&
                 f_1_21.builtin_clone_impls &&
@@ -267,7 +273,8 @@ mod test {
         );
         let f_nightly = RustFeatures::from(RustTarget::Nightly);
         assert!(
-            f_nightly.core_ffi_c_void &&
+            f_nightly.static_lifetime_elision &&
+                f_nightly.core_ffi_c_void &&
                 f_nightly.untagged_union &&
                 f_nightly.associated_const &&
                 f_nightly.builtin_clone_impls &&
@@ -286,6 +293,7 @@ mod test {
     #[test]
     fn str_to_target() {
         test_target("1.0", RustTarget::Stable_1_0);
+        test_target("1.17", RustTarget::Stable_1_17);
         test_target("1.19", RustTarget::Stable_1_19);
         test_target("1.21", RustTarget::Stable_1_21);
         test_target("1.25", RustTarget::Stable_1_25);
diff --git a/tests/expectations/tests/libclang-3.9/constant-evaluate.rs b/tests/expectations/tests/libclang-3.9/constant-evaluate.rs
index 77e28128..b7286a37 100644
--- a/tests/expectations/tests/libclang-3.9/constant-evaluate.rs
+++ b/tests/expectations/tests/libclang-3.9/constant-evaluate.rs
@@ -23,5 +23,5 @@ pub const BAZ: ::std::os::raw::c_longlong = 24;
 pub const fuzz: f64 = 51.0;
 pub const BAZZ: ::std::os::raw::c_char = 53;
 pub const WAT: ::std::os::raw::c_char = 0;
-pub const bytestring: &'static [u8; 4usize] = b"Foo\0";
+pub const bytestring: &[u8; 4usize] = b"Foo\0";
 pub const NOT_UTF8: [u8; 5usize] = [240u8, 40u8, 140u8, 40u8, 0u8];
diff --git a/tests/expectations/tests/libclang-4/constant-evaluate.rs b/tests/expectations/tests/libclang-4/constant-evaluate.rs
index df2638f4..9debe39d 100644
--- a/tests/expectations/tests/libclang-4/constant-evaluate.rs
+++ b/tests/expectations/tests/libclang-4/constant-evaluate.rs
@@ -21,5 +21,5 @@ pub const BAZ: ::std::os::raw::c_longlong = 24;
 pub const fuzz: f64 = 51.0;
 pub const BAZZ: ::std::os::raw::c_char = 53;
 pub const WAT: ::std::os::raw::c_char = 0;
-pub const bytestring: &'static [u8; 4usize] = b"Foo\0";
+pub const bytestring: &[u8; 4usize] = b"Foo\0";
 pub const NOT_UTF8: [u8; 5usize] = [240u8, 40u8, 140u8, 40u8, 0u8];
diff --git a/tests/expectations/tests/libclang-5/constant-evaluate.rs b/tests/expectations/tests/libclang-5/constant-evaluate.rs
index df2638f4..9debe39d 100644
--- a/tests/expectations/tests/libclang-5/constant-evaluate.rs
+++ b/tests/expectations/tests/libclang-5/constant-evaluate.rs
@@ -21,5 +21,5 @@ pub const BAZ: ::std::os::raw::c_longlong = 24;
 pub const fuzz: f64 = 51.0;
 pub const BAZZ: ::std::os::raw::c_char = 53;
 pub const WAT: ::std::os::raw::c_char = 0;
-pub const bytestring: &'static [u8; 4usize] = b"Foo\0";
+pub const bytestring: &[u8; 4usize] = b"Foo\0";
 pub const NOT_UTF8: [u8; 5usize] = [240u8, 40u8, 140u8, 40u8, 0u8];
diff --git a/tests/expectations/tests/libclang-9/constant-evaluate.rs b/tests/expectations/tests/libclang-9/constant-evaluate.rs
index df2638f4..9debe39d 100644
--- a/tests/expectations/tests/libclang-9/constant-evaluate.rs
+++ b/tests/expectations/tests/libclang-9/constant-evaluate.rs
@@ -21,5 +21,5 @@ pub const BAZ: ::std::os::raw::c_longlong = 24;
 pub const fuzz: f64 = 51.0;
 pub const BAZZ: ::std::os::raw::c_char = 53;
 pub const WAT: ::std::os::raw::c_char = 0;
-pub const bytestring: &'static [u8; 4usize] = b"Foo\0";
+pub const bytestring: &[u8; 4usize] = b"Foo\0";
 pub const NOT_UTF8: [u8; 5usize] = [240u8, 40u8, 140u8, 40u8, 0u8];
diff --git a/tests/expectations/tests/macro_const.rs b/tests/expectations/tests/macro_const.rs
index e1356611..de423a2a 100644
--- a/tests/expectations/tests/macro_const.rs
+++ b/tests/expectations/tests/macro_const.rs
@@ -5,7 +5,7 @@
     non_upper_case_globals
 )]
 
-pub const foo: &'static [u8; 4usize] = b"bar\0";
+pub const foo: &[u8; 4usize] = b"bar\0";
 pub const CHAR: u8 = 98u8;
 pub const CHARR: u8 = 0u8;
 pub const FLOAT: f64 = 5.09;
diff --git a/tests/expectations/tests/macro_const_1_0.rs b/tests/expectations/tests/macro_const_1_0.rs
new file mode 100644
index 00000000..e1356611
--- /dev/null
+++ b/tests/expectations/tests/macro_const_1_0.rs
@@ -0,0 +1,14 @@
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
+
+pub const foo: &'static [u8; 4usize] = b"bar\0";
+pub const CHAR: u8 = 98u8;
+pub const CHARR: u8 = 0u8;
+pub const FLOAT: f64 = 5.09;
+pub const FLOAT_EXPR: f64 = 0.005;
+pub const LONG: u32 = 3;
+pub const INVALID_UTF8: [u8; 5usize] = [240u8, 40u8, 140u8, 40u8, 0u8];
diff --git a/tests/headers/macro_const_1_0.h b/tests/headers/macro_const_1_0.h
new file mode 100644
index 00000000..3be86b4f
--- /dev/null
+++ b/tests/headers/macro_const_1_0.h
@@ -0,0 +1,10 @@
+// bindgen-flags: --rust-target 1.0
+
+#define foo "bar"
+#define CHAR 'b'
+#define CHARR '\0'
+#define FLOAT 5.09f
+#define FLOAT_EXPR (5 / 1000.0f)
+#define LONG 3L
+
+#define INVALID_UTF8 "\xf0\x28\x8c\x28"