ir: Handle NonZero and simplify Option<NonZero> like we simplify Option<NonNull>.

Fixes #646

src/bindgen/ir/ty.rs

@@ -517,6 +517,23 @@ impl Type {
         }
     }
 
+    pub fn make_zeroable(&self) -> Option<Self> {
+        let (kind, signed) = match *self {
+            Type::Primitive(PrimitiveType::Integer {
+                zeroable: false,
+                kind,
+                signed,
+            }) => (kind, signed),
+            _ => return None,
+        };
+
+        Some(Type::Primitive(PrimitiveType::Integer {
+            kind,
+            signed,
+            zeroable: true,
+        }))
+    }
+
     pub fn make_nullable(&self) -> Option<Self> {
         match *self {
             Type::Ptr {
@@ -543,12 +560,52 @@ impl Type {
         }
     }
 
+    fn nonzero_to_primitive(&self) -> Option<Self> {
+        let path = match *self {
+            Type::Path(ref p) => p,
+            _ => return None,
+        };
+
+        if !path.generics().is_empty() {
+            return None;
+        }
+
+        let name = path.name();
+        if !name.starts_with("NonZero") {
+            return None;
+        }
+
+        let (kind, signed) = match path.name() {
+            "NonZeroU8" => (IntKind::B8, false),
+            "NonZeroU16" => (IntKind::B16, false),
+            "NonZeroU32" => (IntKind::B32, false),
+            "NonZeroU64" => (IntKind::B64, false),
+            "NonZeroUSize" => (IntKind::Size, false),
+            "NonZeroI8" => (IntKind::B8, true),
+            "NonZeroI16" => (IntKind::B16, true),
+            "NonZeroI32" => (IntKind::B32, true),
+            "NonZeroI64" => (IntKind::B64, true),
+            "NonZeroISize" => (IntKind::Size, true),
+            _ => return None,
+        };
+
+        Some(Type::Primitive(PrimitiveType::Integer {
+            zeroable: false,
+            signed,
+            kind,
+        }))
+    }
+
     fn simplified_type(&self, config: &Config) -> Option<Self> {
         let path = match *self {
             Type::Path(ref p) => p,
             _ => return None,
         };
 
+        if path.generics().is_empty() {
+            return self.nonzero_to_primitive();
+        }
+
         if path.generics().len() != 1 {
             return None;
         }
@@ -559,7 +616,15 @@ impl Type {
             None => Cow::Borrowed(unsimplified_generic),
         };
         match path.name() {
-            "Option" => generic.make_nullable(),
+            "Option" => {
+                if let Some(nullable) = generic.make_nullable() {
+                    return Some(nullable);
+                }
+                if let Some(zeroable) = generic.make_zeroable() {
+                    return Some(zeroable);
+                }
+                None
+            }
             "NonNull" => Some(Type::Ptr {
                 ty: Box::new(generic.into_owned()),
                 is_const: false,

tests/expectations/nonzero.both.c

@@ -0,0 +1,44 @@
+#if 0
+''' '
+#endif
+
+#ifdef __cplusplus
+struct NonZeroI64;
+#endif
+
+#if 0
+' '''
+#endif
+
+
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+typedef struct Option_Option_NonZeroI64 Option_Option_NonZeroI64;
+
+typedef struct NonZeroTest {
+  uint8_t a;
+  uint16_t b;
+  uint32_t c;
+  uint64_t d;
+  int8_t e;
+  int16_t f;
+  int32_t g;
+  int64_t h;
+  int64_t i;
+  const struct Option_Option_NonZeroI64 *j;
+} NonZeroTest;
+
+void root(struct NonZeroTest test,
+          uint8_t a,
+          uint16_t b,
+          uint32_t c,
+          uint64_t d,
+          int8_t e,
+          int16_t f,
+          int32_t g,
+          int64_t h,
+          int64_t i,
+          const struct Option_Option_NonZeroI64 *j);

tests/expectations/nonzero.both.compat.c

@@ -0,0 +1,52 @@
+#if 0
+''' '
+#endif
+
+#ifdef __cplusplus
+struct NonZeroI64;
+#endif
+
+#if 0
+' '''
+#endif
+
+
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+typedef struct Option_Option_NonZeroI64 Option_Option_NonZeroI64;
+
+typedef struct NonZeroTest {
+  uint8_t a;
+  uint16_t b;
+  uint32_t c;
+  uint64_t d;
+  int8_t e;
+  int16_t f;
+  int32_t g;
+  int64_t h;
+  int64_t i;
+  const struct Option_Option_NonZeroI64 *j;
+} NonZeroTest;
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+void root(struct NonZeroTest test,
+          uint8_t a,
+          uint16_t b,
+          uint32_t c,
+          uint64_t d,
+          int8_t e,
+          int16_t f,
+          int32_t g,
+          int64_t h,
+          int64_t i,
+          const struct Option_Option_NonZeroI64 *j);
+
+#ifdef __cplusplus
+} // extern "C"
+#endif // __cplusplus

tests/expectations/nonzero.c

@@ -0,0 +1,44 @@
+#if 0
+''' '
+#endif
+
+#ifdef __cplusplus
+struct NonZeroI64;
+#endif
+
+#if 0
+' '''
+#endif
+
+
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+typedef struct Option_Option_NonZeroI64 Option_Option_NonZeroI64;
+
+typedef struct {
+  uint8_t a;
+  uint16_t b;
+  uint32_t c;
+  uint64_t d;
+  int8_t e;
+  int16_t f;
+  int32_t g;
+  int64_t h;
+  int64_t i;
+  const Option_Option_NonZeroI64 *j;
+} NonZeroTest;
+
+void root(NonZeroTest test,
+          uint8_t a,
+          uint16_t b,
+          uint32_t c,
+          uint64_t d,
+          int8_t e,
+          int16_t f,
+          int32_t g,
+          int64_t h,
+          int64_t i,
+          const Option_Option_NonZeroI64 *j);

tests/expectations/nonzero.compat.c

@@ -0,0 +1,52 @@
+#if 0
+''' '
+#endif
+
+#ifdef __cplusplus
+struct NonZeroI64;
+#endif
+
+#if 0
+' '''
+#endif
+
+
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+typedef struct Option_Option_NonZeroI64 Option_Option_NonZeroI64;
+
+typedef struct {
+  uint8_t a;
+  uint16_t b;
+  uint32_t c;
+  uint64_t d;
+  int8_t e;
+  int16_t f;
+  int32_t g;
+  int64_t h;
+  int64_t i;
+  const Option_Option_NonZeroI64 *j;
+} NonZeroTest;
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+void root(NonZeroTest test,
+          uint8_t a,
+          uint16_t b,
+          uint32_t c,
+          uint64_t d,
+          int8_t e,
+          int16_t f,
+          int32_t g,
+          int64_t h,
+          int64_t i,
+          const Option_Option_NonZeroI64 *j);
+
+#ifdef __cplusplus
+} // extern "C"
+#endif // __cplusplus

tests/expectations/nonzero.cpp

@@ -0,0 +1,50 @@
+#if 0
+''' '
+#endif
+
+#ifdef __cplusplus
+struct NonZeroI64;
+#endif
+
+#if 0
+' '''
+#endif
+
+
+#include <cstdarg>
+#include <cstdint>
+#include <cstdlib>
+#include <ostream>
+#include <new>
+
+template<typename T = void>
+struct Option;
+
+struct NonZeroTest {
+  uint8_t a;
+  uint16_t b;
+  uint32_t c;
+  uint64_t d;
+  int8_t e;
+  int16_t f;
+  int32_t g;
+  int64_t h;
+  int64_t i;
+  const Option<Option<NonZeroI64>> *j;
+};
+
+extern "C" {
+
+void root(NonZeroTest test,
+          uint8_t a,
+          uint16_t b,
+          uint32_t c,
+          uint64_t d,
+          int8_t e,
+          int16_t f,
+          int32_t g,
+          int64_t h,
+          int64_t i,
+          const Option<Option<NonZeroI64>> *j);
+
+} // extern "C"

tests/expectations/nonzero.pyx

@@ -0,0 +1,47 @@
+#if 0
+''' '
+#endif
+
+#ifdef __cplusplus
+struct NonZeroI64;
+#endif
+
+#if 0
+' '''
+#endif
+
+
+from libc.stdint cimport int8_t, int16_t, int32_t, int64_t, intptr_t
+from libc.stdint cimport uint8_t, uint16_t, uint32_t, uint64_t, uintptr_t
+cdef extern from *:
+  ctypedef bint bool
+  ctypedef struct va_list
+
+cdef extern from *:
+
+  ctypedef struct Option_Option_NonZeroI64:
+    pass
+
+  ctypedef struct NonZeroTest:
+    uint8_t a;
+    uint16_t b;
+    uint32_t c;
+    uint64_t d;
+    int8_t e;
+    int16_t f;
+    int32_t g;
+    int64_t h;
+    int64_t i;
+    const Option_Option_NonZeroI64 *j;
+
+  void root(NonZeroTest test,
+            uint8_t a,
+            uint16_t b,
+            uint32_t c,
+            uint64_t d,
+            int8_t e,
+            int16_t f,
+            int32_t g,
+            int64_t h,
+            int64_t i,
+            const Option_Option_NonZeroI64 *j);

tests/expectations/nonzero.tag.c

@@ -0,0 +1,44 @@
+#if 0
+''' '
+#endif
+
+#ifdef __cplusplus
+struct NonZeroI64;
+#endif
+
+#if 0
+' '''
+#endif
+
+
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+struct Option_Option_NonZeroI64;
+
+struct NonZeroTest {
+  uint8_t a;
+  uint16_t b;
+  uint32_t c;
+  uint64_t d;
+  int8_t e;
+  int16_t f;
+  int32_t g;
+  int64_t h;
+  int64_t i;
+  const struct Option_Option_NonZeroI64 *j;
+};
+
+void root(struct NonZeroTest test,
+          uint8_t a,
+          uint16_t b,
+          uint32_t c,
+          uint64_t d,
+          int8_t e,
+          int16_t f,
+          int32_t g,
+          int64_t h,
+          int64_t i,
+          const struct Option_Option_NonZeroI64 *j);

tests/expectations/nonzero.tag.compat.c

@@ -0,0 +1,52 @@
+#if 0
+''' '
+#endif
+
+#ifdef __cplusplus
+struct NonZeroI64;
+#endif
+
+#if 0
+' '''
+#endif
+
+
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+struct Option_Option_NonZeroI64;
+
+struct NonZeroTest {
+  uint8_t a;
+  uint16_t b;
+  uint32_t c;
+  uint64_t d;
+  int8_t e;
+  int16_t f;
+  int32_t g;
+  int64_t h;
+  int64_t i;
+  const struct Option_Option_NonZeroI64 *j;
+};
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+void root(struct NonZeroTest test,
+          uint8_t a,
+          uint16_t b,
+          uint32_t c,
+          uint64_t d,
+          int8_t e,
+          int16_t f,
+          int32_t g,
+          int64_t h,
+          int64_t i,
+          const struct Option_Option_NonZeroI64 *j);
+
+#ifdef __cplusplus
+} // extern "C"
+#endif // __cplusplus

tests/expectations/nonzero.tag.pyx

@@ -0,0 +1,47 @@
+#if 0
+''' '
+#endif
+
+#ifdef __cplusplus
+struct NonZeroI64;
+#endif
+
+#if 0
+' '''
+#endif
+
+
+from libc.stdint cimport int8_t, int16_t, int32_t, int64_t, intptr_t
+from libc.stdint cimport uint8_t, uint16_t, uint32_t, uint64_t, uintptr_t
+cdef extern from *:
+  ctypedef bint bool
+  ctypedef struct va_list
+
+cdef extern from *:
+
+  cdef struct Option_Option_NonZeroI64:
+    pass
+
+  cdef struct NonZeroTest:
+    uint8_t a;
+    uint16_t b;
+    uint32_t c;
+    uint64_t d;
+    int8_t e;
+    int16_t f;
+    int32_t g;
+    int64_t h;
+    int64_t i;
+    const Option_Option_NonZeroI64 *j;
+
+  void root(NonZeroTest test,
+            uint8_t a,
+            uint16_t b,
+            uint32_t c,
+            uint64_t d,
+            int8_t e,
+            int16_t f,
+            int32_t g,
+            int64_t h,
+            int64_t i,
+            const Option_Option_NonZeroI64 *j);

tests/rust/nonzero.rs

@@ -0,0 +1,30 @@
+use std::num::*;
+
+#[repr(C)]
+pub struct NonZeroTest {
+    pub a: NonZeroU8,
+    pub b: NonZeroU16,
+    pub c: NonZeroU32,
+    pub d: NonZeroU64,
+    pub e: NonZeroI8,
+    pub f: NonZeroI16,
+    pub g: NonZeroI32,
+    pub h: NonZeroI64,
+    pub i: Option<NonZeroI64>,
+    pub j: *const Option<Option<NonZeroI64>>,
+}
+
+#[no_mangle]
+pub extern "C" fn root(
+    test: NonZeroTest,
+    a: NonZeroU8,
+    b: NonZeroU16,
+    c: NonZeroU32,
+    d: NonZeroU64,
+    e: NonZeroI8,
+    f: NonZeroI16,
+    g: NonZeroI32,
+    h: NonZeroI64,
+    i: Option<NonZeroI64>,
+    j: *const Option<Option<NonZeroI64>>,
+) {}

tests/rust/nonzero.toml

@@ -0,0 +1,13 @@
+header = """
+#if 0
+''' '
+#endif
+
+#ifdef __cplusplus
+struct NonZeroI64;
+#endif
+
+#if 0
+' '''
+#endif
+"""