From 63b78c86d93484a3721c53faf9bd60311063b64f Mon Sep 17 00:00:00 2001
From: Paolo Teti <paolo.teti@gmail.com>
Date: Fri, 16 Feb 2018 17:31:25 +0100
Subject: [PATCH] Fix thumbv6m build (feature=c)

1. Avoid undefined references as:
   undefined reference to `__modsi3'
   undefined reference to `__umodsi3'

2. We can't remove assembly implementations that are not in the list
---
 library/compiler-builtins/build.rs        | 5 -----
 library/compiler-builtins/src/int/sdiv.rs | 7 +++++--
 library/compiler-builtins/src/int/udiv.rs | 4 +++-
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/library/compiler-builtins/build.rs b/library/compiler-builtins/build.rs
index 594afbded81..9eca26c1dd9 100644
--- a/library/compiler-builtins/build.rs
+++ b/library/compiler-builtins/build.rs
@@ -423,13 +423,8 @@ mod c {
         if llvm_target[0] == "thumbv6m" {
             sources.remove(
                 &[
-                    "aeabi_cdcmp",
-                    "aeabi_cfcmp",
-                    "aeabi_dcmp",
-                    "aeabi_fcmp",
                     "clzdi2",
                     "clzsi2",
-                    "comparesf2",
                     "divmodsi4",
                     "modsi3",
                     "switch16",
diff --git a/library/compiler-builtins/src/int/sdiv.rs b/library/compiler-builtins/src/int/sdiv.rs
index 2f09bd51d91..2de73b0eab7 100644
--- a/library/compiler-builtins/src/int/sdiv.rs
+++ b/library/compiler-builtins/src/int/sdiv.rs
@@ -72,7 +72,9 @@ intrinsics! {
         a.div(b)
     }
 
-    #[use_c_shim_if(all(target_arch = "arm", not(target_os = "ios")))]
+    #[use_c_shim_if(all(target_arch = "arm",
+                    not(target_os = "ios")),
+                    not(thumbv6m))]
     pub extern "C" fn __modsi3(a: i32, b: i32) -> i32 {
         a.mod_(b)
     }
@@ -87,7 +89,8 @@ intrinsics! {
         a.mod_(b)
     }
 
-    #[use_c_shim_if(all(target_arch = "arm", not(target_os = "ios")))]
+    #[use_c_shim_if(all(target_arch = "arm",
+                    not(target_os = "ios"), not(thumbv6m)))]
     pub extern "C" fn __divmodsi4(a: i32, b: i32, rem: &mut i32) -> i32 {
         a.divmod(b, rem, |a, b| __divsi3(a, b))
     }
diff --git a/library/compiler-builtins/src/int/udiv.rs b/library/compiler-builtins/src/int/udiv.rs
index 1d93e177b5b..4382460e782 100644
--- a/library/compiler-builtins/src/int/udiv.rs
+++ b/library/compiler-builtins/src/int/udiv.rs
@@ -209,7 +209,9 @@ intrinsics! {
         (q << 1) | carry
     }
 
-    #[use_c_shim_if(all(target_arch = "arm", not(target_os = "ios")))]
+    #[use_c_shim_if(all(target_arch = "arm",
+                        not(target_os = "ios"),
+                        not(thumbv6m)))]
     /// Returns `n % d`
     pub extern "C" fn __umodsi3(n: u32, d: u32) -> u32 {
         let q = __udivsi3(n, d);