From e2114642ae0b70aaf9b2036fbf26245106aa22e8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Emilio=20Cobos=20=C3=81lvarez?= <emilio@crisal.io>
Date: Sun, 14 Apr 2024 21:39:23 -0400
Subject: [PATCH] parser: Treat omitted ABI in extern block as "C".

As per https://doc.rust-lang.org/reference/items/external-blocks.html#abi

Closes #709
---
 src/bindgen/parser.rs                   | 2 +-
 tests/expectations/extern.c             | 2 ++
 tests/expectations/extern.compat.c      | 2 ++
 tests/expectations/extern.cpp           | 2 ++
 tests/expectations/extern.pyx           | 2 ++
 tests/expectations/extern_both.c        | 2 ++
 tests/expectations/extern_both.compat.c | 2 ++
 tests/expectations/extern_tag.c         | 2 ++
 tests/expectations/extern_tag.compat.c  | 2 ++
 tests/expectations/extern_tag.pyx       | 2 ++
 tests/rust/extern.rs                    | 4 ++++
 11 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/src/bindgen/parser.rs b/src/bindgen/parser.rs
index ddc3672a8..c418e9d2a 100644
--- a/src/bindgen/parser.rs
+++ b/src/bindgen/parser.rs
@@ -600,7 +600,7 @@ impl Parse {
         mod_cfg: Option<&Cfg>,
         item: &syn::ItemForeignMod,
     ) {
-        if !item.abi.is_c() {
+        if !item.abi.is_c() && !item.abi.is_omitted() {
             info!("Skip {} - (extern block must be extern C).", crate_name);
             return;
         }
diff --git a/tests/expectations/extern.c b/tests/expectations/extern.c
index 6fe9f5bdb..70b2a3be9 100644
--- a/tests/expectations/extern.c
+++ b/tests/expectations/extern.c
@@ -11,3 +11,5 @@ typedef struct {
 extern int32_t foo(void);
 
 extern void bar(Normal a);
+
+extern int32_t baz(void);
diff --git a/tests/expectations/extern.compat.c b/tests/expectations/extern.compat.c
index 4f4129ad5..7cf348439 100644
--- a/tests/expectations/extern.compat.c
+++ b/tests/expectations/extern.compat.c
@@ -16,6 +16,8 @@ extern int32_t foo(void);
 
 extern void bar(Normal a);
 
+extern int32_t baz(void);
+
 #ifdef __cplusplus
 } // extern "C"
 #endif // __cplusplus
diff --git a/tests/expectations/extern.cpp b/tests/expectations/extern.cpp
index 15294c05c..ecdea3c11 100644
--- a/tests/expectations/extern.cpp
+++ b/tests/expectations/extern.cpp
@@ -15,4 +15,6 @@ extern int32_t foo();
 
 extern void bar(Normal a);
 
+extern int32_t baz();
+
 } // extern "C"
diff --git a/tests/expectations/extern.pyx b/tests/expectations/extern.pyx
index dca17ac8f..51b05833c 100644
--- a/tests/expectations/extern.pyx
+++ b/tests/expectations/extern.pyx
@@ -13,3 +13,5 @@ cdef extern from *:
   extern int32_t foo();
 
   extern void bar(Normal a);
+
+  extern int32_t baz();
diff --git a/tests/expectations/extern_both.c b/tests/expectations/extern_both.c
index 026661a64..56aad04ef 100644
--- a/tests/expectations/extern_both.c
+++ b/tests/expectations/extern_both.c
@@ -11,3 +11,5 @@ typedef struct Normal {
 extern int32_t foo(void);
 
 extern void bar(struct Normal a);
+
+extern int32_t baz(void);
diff --git a/tests/expectations/extern_both.compat.c b/tests/expectations/extern_both.compat.c
index 3c49da31e..dff58551d 100644
--- a/tests/expectations/extern_both.compat.c
+++ b/tests/expectations/extern_both.compat.c
@@ -16,6 +16,8 @@ extern int32_t foo(void);
 
 extern void bar(struct Normal a);
 
+extern int32_t baz(void);
+
 #ifdef __cplusplus
 } // extern "C"
 #endif // __cplusplus
diff --git a/tests/expectations/extern_tag.c b/tests/expectations/extern_tag.c
index 5a88d1a22..e70c271a2 100644
--- a/tests/expectations/extern_tag.c
+++ b/tests/expectations/extern_tag.c
@@ -11,3 +11,5 @@ struct Normal {
 extern int32_t foo(void);
 
 extern void bar(struct Normal a);
+
+extern int32_t baz(void);
diff --git a/tests/expectations/extern_tag.compat.c b/tests/expectations/extern_tag.compat.c
index 3ca162513..a2d9ea961 100644
--- a/tests/expectations/extern_tag.compat.c
+++ b/tests/expectations/extern_tag.compat.c
@@ -16,6 +16,8 @@ extern int32_t foo(void);
 
 extern void bar(struct Normal a);
 
+extern int32_t baz(void);
+
 #ifdef __cplusplus
 } // extern "C"
 #endif // __cplusplus
diff --git a/tests/expectations/extern_tag.pyx b/tests/expectations/extern_tag.pyx
index 9cb7214a4..f62773325 100644
--- a/tests/expectations/extern_tag.pyx
+++ b/tests/expectations/extern_tag.pyx
@@ -13,3 +13,5 @@ cdef extern from *:
   extern int32_t foo();
 
   extern void bar(Normal a);
+
+  extern int32_t baz();
diff --git a/tests/rust/extern.rs b/tests/rust/extern.rs
index 3bd83d17f..e9a93920e 100644
--- a/tests/rust/extern.rs
+++ b/tests/rust/extern.rs
@@ -9,3 +9,7 @@ extern "C" {
 
     fn bar(a: Normal);
 }
+
+extern {
+    fn baz() -> i32;
+}