Define c_char at top-level and remove per-target c_char definitions

(backport <#4202>)
(cherry picked from commit 0a02b94)

Author: taiki-e

libc-test/build.rs

@@ -364,9 +364,6 @@ fn test_apple(target: &str) {
             // FIXME: "'__uint128' undeclared" in C
             "__uint128" => true,
 
-            // `c_char_def` is always public but not always reexported.
-            "c_char_def" => true,
-
             _ => false,
         }
     });
@@ -766,8 +763,6 @@ fn test_windows(target: &str) {
         "ssize_t" if !gnu => true,
         // FIXME: The size and alignment of this type are incorrect
         "time_t" if gnu && i686 => true,
-        // `c_char_def` is always public but not always reexported.
-        "c_char_def" => true,
         _ => false,
     });
 
@@ -985,8 +980,6 @@ fn test_solarish(target: &str) {
 
     cfg.skip_type(move |ty| match ty {
         "sighandler_t" => true,
-        // `c_char_def` is always public but not always reexported.
-        "c_char_def" => true,
         _ => false,
     });
 
@@ -1290,8 +1283,6 @@ fn test_netbsd(target: &str) {
         match ty {
             // FIXME: sighandler_t is crazy across platforms
             "sighandler_t" => true,
-            // `c_char_def` is always public but not always reexported.
-            "c_char_def" => true,
             _ => false,
         }
     });
@@ -1511,8 +1502,6 @@ fn test_dragonflybsd(target: &str) {
         match ty {
             // sighandler_t is crazy across platforms
             "sighandler_t" => true,
-            // `c_char_def` is always public but not always reexported.
-            "c_char_def" => true,
             _ => false,
         }
     });
@@ -1674,8 +1663,6 @@ fn test_wasi(target: &str) {
         }
     });
 
-    cfg.skip_type(|ty| ty == "c_char_def");
-
     // These have a different and internal type in header files and are only
     // used here to generate a pointer to them in bindings so skip these tests.
     cfg.skip_static(|c| c.starts_with("_CLOCK_"));
@@ -1924,9 +1911,6 @@ fn test_android(target: &str) {
             // FIXME: "'__uint128' undeclared" in C
             "__uint128" => true,
 
-            // `c_char_def` is always public but not always reexported.
-            "c_char_def" => true,
-
             _ => false,
         }
     });
@@ -2689,9 +2673,6 @@ fn test_freebsd(target: &str) {
             // `eventfd(2)` and things come with it are added in FreeBSD 13
             "eventfd_t" if Some(13) > freebsd_ver => true,
 
-            // `c_char_def` is always public but not always reexported.
-            "c_char_def" => true,
-
             _ => false,
         }
     });
@@ -3012,9 +2993,6 @@ fn test_emscripten(target: &str) {
             // https://github.com/emscripten-core/emscripten/issues/5033
             ty if ty.starts_with("epoll") => true,
 
-            // `c_char_def` is always public but not always reexported.
-            "c_char_def" => true,
-
             // LFS64 types have been removed in Emscripten 3.1.44
             // https://github.com/emscripten-core/emscripten/pull/19812
             t => t.ends_with("64") || t.ends_with("64_t"),
@@ -3286,9 +3264,6 @@ fn test_neutrino(target: &str) {
             // Does not exist in Neutrino
             "locale_t" => true,
 
-            // `c_char_def` is always public but not always reexported.
-            "c_char_def" => true,
-
             _ => false,
         }
     });
@@ -3455,8 +3430,6 @@ fn test_vxworks(target: &str) {
     // FIXME
     cfg.skip_type(move |ty| match ty {
         "stat64" | "sighandler_t" | "off64_t" => true,
-        // `c_char_def` is always public but not always reexported.
-        "c_char_def" => true,
         _ => false,
     });
 
@@ -3804,9 +3777,6 @@ fn test_linux(target: &str) {
             // FIXME: "'__uint128' undeclared" in C
             "__uint128" => true,
 
-            // `c_char_def` is always public but not always reexported.
-            "c_char_def" => true,
-
             t => {
                 if musl {
                     // LFS64 types have been removed in musl 1.2.4+
@@ -4036,7 +4006,7 @@ fn test_linux(target: &str) {
             }
             // FIXME: Requires >= 5.4 kernel headers
             if name == "PTP_CLOCK_GETCAPS2"
-                || name == "PTP_ENABLE_PPS2" 
+                || name == "PTP_ENABLE_PPS2"
                 || name == "PTP_EXTTS_REQUEST2"
                 || name == "PTP_PEROUT_REQUEST2"
                 || name == "PTP_PIN_GETFUNC2"
@@ -4759,8 +4729,6 @@ fn test_linux_like_apis(target: &str) {
             })
             .skip_type(move |ty| match ty {
                 "Elf64_Phdr" | "Elf32_Phdr" => false,
-                // `c_char_def` is always public but not always reexported.
-                "c_char_def" => true,
                 _ => true,
             });
         cfg.generate(src_hotfix_dir().join("lib.rs"), "linux_elf.rs");
@@ -4996,8 +4964,6 @@ fn test_haiku(target: &str) {
             "pthread_condattr_t" => true,
             "pthread_mutexattr_t" => true,
             "pthread_rwlockattr_t" => true,
-            // `c_char_def` is always public but not always reexported.
-            "c_char_def" => true,
             _ => false,
         }
     });

src/fuchsia/aarch64.rs

@@ -1,7 +1,6 @@
 use crate::off_t;
 use crate::prelude::*;
 
-pub type c_char = u8;
 pub type __u64 = c_ulonglong;
 pub type wchar_t = u32;
 pub type nlink_t = c_ulong;

src/fuchsia/riscv64.rs

@@ -2,7 +2,6 @@ use crate::off_t;
 use crate::prelude::*;
 
 // From psABI Calling Convention for RV64
-pub type c_char = u8;
 pub type __u64 = c_ulonglong;
 pub type wchar_t = i32;
 

src/fuchsia/x86_64.rs

@@ -1,7 +1,6 @@
 use crate::off_t;
 use crate::prelude::*;
 
-pub type c_char = i8;
 pub type wchar_t = i32;
 pub type nlink_t = u64;
 pub type blksize_t = c_long;

src/hermit.rs

@@ -1,6 +1,5 @@
 //! Hermit C type definitions
 
-pub use crate::arch::c_char_def as c_char;
 use crate::prelude::*;
 
 pub type c_schar = i8;

src/lib.rs

@@ -41,41 +41,35 @@ cfg_if! {
 
 pub use core::ffi::c_void;
 
-/// Type definitions that are coupled tighter to architecture than OS.
-mod arch {
-    cfg_if! {
-        // This configuration comes from `rust-lang/rust` in `library/core/src/ffi/mod.rs`.
-        if #[cfg(all(
-            not(windows),
-            // FIXME(ctest): just use `target_vendor` = "apple"` once `ctest` supports it
-            not(any(
-                target_os = "macos",
-                target_os = "ios",
-                target_os = "tvos",
-                target_os = "watchos",
-                target_os = "visionos",
-            )),
-            any(
-                target_arch = "aarch64",
-                target_arch = "arm",
-                target_arch = "csky",
-                target_arch = "hexagon",
-                target_arch = "msp430",
-                target_arch = "powerpc",
-                target_arch = "powerpc64",
-                target_arch = "riscv64",
-                target_arch = "riscv32",
-                target_arch = "s390x",
-                target_arch = "xtensa",
-            )
-        ))] {
-            // To be reexported as `c_char`
-            // FIXME(ctest): just name these `c_char` once `ctest` learns that these don't get
-            // exported.
-            pub type c_char_def = u8;
-        } else {
-            pub type c_char_def = i8;
-        }
+cfg_if! {
+    // This configuration comes from `rust-lang/rust` in `library/core/src/ffi/mod.rs`.
+    if #[cfg(all(
+        not(windows),
+        // FIXME(ctest): just use `target_vendor` = "apple"` once `ctest` supports it
+        not(any(
+            target_os = "macos",
+            target_os = "ios",
+            target_os = "tvos",
+            target_os = "watchos",
+            target_os = "visionos",
+        )),
+        any(
+            target_arch = "aarch64",
+            target_arch = "arm",
+            target_arch = "csky",
+            target_arch = "hexagon",
+            target_arch = "msp430",
+            target_arch = "powerpc",
+            target_arch = "powerpc64",
+            target_arch = "riscv64",
+            target_arch = "riscv32",
+            target_arch = "s390x",
+            target_arch = "xtensa",
+        )
+    ))] {
+        pub type c_char = u8;
+    } else {
+        pub type c_char = i8;
     }
 }
 

src/sgx.rs

@@ -19,7 +19,6 @@ pub type intptr_t = isize;
 pub type uintptr_t = usize;
 pub type ssize_t = isize;
 
-pub type c_char = i8;
 pub type c_long = i64;
 pub type c_ulong = u64;
 

src/solid/aarch64.rs

@@ -1,4 +1,3 @@
-pub type c_char = u8;
 pub type wchar_t = u32;
 pub type c_long = i64;
 pub type c_ulong = u64;

src/solid/arm.rs

@@ -1,4 +1,3 @@
-pub type c_char = u8;
 pub type wchar_t = u32;
 pub type c_long = i32;
 pub type c_ulong = u32;

src/switch.rs

@@ -20,7 +20,6 @@ pub type uintptr_t = usize;
 pub type ssize_t = isize;
 
 pub type off_t = i64;
-pub type c_char = u8;
 pub type c_long = i64;
 pub type c_ulong = u64;
 pub type wchar_t = u32;