teach travis how to test thumb* targets

Author: Jorge Aparicio

build.rs

@@ -408,4 +408,9 @@ fn main() {
     if llvm_target.last() == Some(&"gnueabihf") {
         println!("cargo:rustc-cfg=gnueabihf")
     }
+
+    // To compile intrinsics.rs for thumb targets, where there is no libc
+    if llvm_target[0].starts_with("thumb") {
+        println!("cargo:rustc-cfg=thumb")
+    }
 }

ci/env.sh

@@ -41,6 +41,8 @@ if [[ $TARGET != $HOST && ! $TARGET =~ ^i.86- ]]; then
     esac
 
     export CARGO_TARGET_$(echo $TARGET | tr a-z- A-Z_)_LINKER=$GCC_TRIPLE-gcc
+    export AR_$(echo $TARGET | tr - _)=$GCC_TRIPLE-ar
+    export CC_$(echo $TARGET | tr - _)=$GCC_TRIPLE-gcc
 
     if [[ $RUN_TESTS == y ]]; then
         # NOTE(export) so this can reach the processes that `cargo test` spawns

src/bin/intrinsics.rs

@@ -10,7 +10,9 @@
 #![feature(libc)]
 #![feature(start)]
 #![no_std]
+#![cfg_attr(thumb, no_main)]
 
+#[cfg(not(thumb))]
 extern crate libc;
 extern crate rustc_builtins;
 
@@ -236,8 +238,7 @@ mod intrinsics {
 }
 
 #[cfg(feature = "c")]
-#[start]
-fn main(_: isize, _: *const *const u8) -> isize {
+fn run() {
     use intrinsics::*;
 
     aeabi_d2f(2.);
@@ -284,16 +285,35 @@ fn main(_: isize, _: *const *const u8) -> isize {
     powidf2(2., 3);
     powisf2(2., 3);
     umoddi3(2, 3);
+}
+
+#[cfg(all(feature = "c", not(thumb)))]
+#[start]
+fn main(_: isize, _: *const *const u8) -> isize {
+    run();
 
     0
 }
 
-#[cfg(not(feature = "c"))]
+#[cfg(all(not(feature = "c"), not(thumb)))]
 #[start]
 fn main(_: isize, _: *const *const u8) -> isize {
     0
 }
 
+#[cfg(all(feature = "c", thumb))]
+#[no_mangle]
+pub fn _start() -> ! {
+    run();
+    loop {}
+}
+
+#[cfg(all(not(feature = "c"), thumb))]
+#[no_mangle]
+pub fn _start() -> ! {
+    loop {}
+}
+
 // ARM targets need these symbols
 #[no_mangle]
 pub fn __aeabi_unwind_cpp_pr0() {}

thumbv6m-none-eabi.json

@@ -1,10 +1,12 @@
 {
     "arch": "arm",
     "data-layout": "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64",
+    "executables": true,
     "features": "+strict-align",
     "llvm-target": "thumbv6m-none-eabi",
     "max-atomic-width": 0,
     "os": "none",
+    "pre-link-args": ["-nostartfiles"],
     "target-endian": "little",
     "target-pointer-width": "32"
 }

thumbv7em-none-eabi.json

@@ -1,8 +1,10 @@
 {
     "arch": "arm",
     "data-layout": "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64",
+    "executables": true,
     "llvm-target": "thumbv7em-none-eabi",
     "os": "none",
+    "pre-link-args": ["-nostartfiles"],
     "target-endian": "little",
     "target-pointer-width": "32"
 }

thumbv7em-none-eabihf.json

@@ -1,9 +1,11 @@
 {
     "arch": "arm",
     "data-layout": "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64",
+    "executables": true,
     "features": "+vfp4",
     "llvm-target": "thumbv7em-none-eabihf",
     "os": "none",
+    "pre-link-args": ["-nostartfiles"],
     "target-endian": "little",
     "target-pointer-width": "32"
 }

thumbv7m-none-eabi.json

@@ -1,8 +1,10 @@
 {
     "arch": "arm",
     "data-layout": "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64",
+    "executables": true,
     "llvm-target": "thumbv7m-none-eabi",
     "os": "none",
+    "pre-link-args": ["-nostartfiles"],
     "target-endian": "little",
     "target-pointer-width": "32"
 }