[bindings] Use the same SipHash keys to make C++ header stable

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index f1e519bee8a126878852a339ad96a5138bee9baa..bafdd29fffd975a7ae5ab1585e224de279ea2729 100644 (file)
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -173,15 +173,7 @@ jobs:
             cat lightning-c-bindings/include/lightning.h | grep -v "Generated with cbindgen:[0-9\.]*" | sort > lightning-c-bindings/include/lightning.h.sorted
             cat lightning-c-bindings/include/lightning.h.new | grep -v "Generated with cbindgen:[0-9\.]*" | sort > lightning-c-bindings/include/lightning.h.new.sorted
             diff lightning-c-bindings/include/lightning.h.sorted lightning-c-bindings/include/lightning.h.new.sorted
-            #
-            mv lightning-c-bindings/include/lightningpp.hpp lightning-c-bindings/include/lightningpp.hpp.new
-            git checkout lightning-c-bindings/include/lightningpp.hpp
-            cat lightning-c-bindings/include/lightningpp.hpp | sort > lightning-c-bindings/include/lightningpp.hpp.sorted
-            cat lightning-c-bindings/include/lightningpp.hpp.new | sort > lightning-c-bindings/include/lightningpp.hpp.new.sorted
-            diff lightning-c-bindings/include/lightningpp.hpp.sorted lightning-c-bindings/include/lightningpp.hpp.new.sorted
-            #
             [ "$(diff lightning-c-bindings/include/lightning.h.sorted lightning-c-bindings/include/lightning.h.new.sorted)" != "" ] && exit 2
-            [ "$(diff lightning-c-bindings/include/lightningpp.hpp.sorted lightning-c-bindings/include/lightningpp.hpp.new.sorted)" != "" ] && exit 3
             git diff --exit-code
           fi
 

diff --git a/c-bindings-gen/src/main.rs b/c-bindings-gen/src/main.rs
index 611607ede646baa8f761ba53552a38d9148266bc..fed13f11c20a0b8e90c6899e93b939287dc76f9a 100644 (file)
--- a/c-bindings-gen/src/main.rs
+++ b/c-bindings-gen/src/main.rs
@@ -1350,7 +1350,7 @@ fn main() {
        // ...then walk the ASTs tracking what types we will map, and how, so that we can resolve them
        // when parsing other file ASTs...
        let mut libtypes = CrateTypes { traits: HashMap::new(), opaques: HashMap::new(), mirrored_enums: HashMap::new(),
-               type_aliases: HashMap::new(), templates_defined: HashMap::new(), template_file: &mut derived_templates };
+               type_aliases: HashMap::new(), templates_defined: HashMap::default(), template_file: &mut derived_templates };
        walk_ast(&args[1], "/lib.rs", "".to_string(), &libast, &mut libtypes);
 
        // ... finally, do the actual file conversion/mapping, writing out types as we go.

diff --git a/c-bindings-gen/src/types.rs b/c-bindings-gen/src/types.rs
index 973d1909ef9215287baef561fb6cf139fb13052c..32036180d69d8282236fa3e8002696698fbd0d4c 100644 (file)
--- a/c-bindings-gen/src/types.rs
+++ b/c-bindings-gen/src/types.rs
@@ -1,6 +1,7 @@
 use std::collections::HashMap;
 use std::fs::File;
 use std::io::Write;
+use std::hash;
 
 use proc_macro2::{TokenTree, Span};
 
@@ -225,6 +226,13 @@ pub enum DeclType<'a> {
        EnumIgnored,
 }
 
+// templates_defined is walked to write the C++ header, so if we use the default hashing it get
+// reordered on each genbindings run. Instead, we use SipHasher (which defaults to 0-keys) so that
+// the sorting is stable across runs. It is deprecated, but the "replacement" doesn't actually
+// accomplish the same goals, so we just ignore it.
+#[allow(deprecated)]
+type NonRandomHash = hash::BuildHasherDefault<hash::SipHasher>;
+
 /// Top-level struct tracking everything which has been defined while walking the crate.
 pub struct CrateTypes<'a> {
        /// This may contain structs or enums, but only when either is mapped as
@@ -240,7 +248,7 @@ pub struct CrateTypes<'a> {
        /// exists.
        ///
        /// This is used at the end of processing to make C++ wrapper classes
-       pub templates_defined: HashMap<String, bool>,
+       pub templates_defined: HashMap<String, bool, NonRandomHash>,
        /// The output file for any created template container types, written to as we find new
        /// template containers which need to be defined.
        pub template_file: &'a mut File,