[gcc/devel/rust/master] gccrs: allow casts from numeric types to floats

[Thomas Schwinge via Gcc-cvs]

https://gcc.gnu.org/g:2aff74974ec2400dbccc103d8f05d9e14def87b3

commit 2aff74974ec2400dbccc103d8f05d9e14def87b3
Author: Philip Herron <herron.phi...@googlemail.com>
Date:   Tue Nov 26 15:33:35 2024 +0000

    gccrs: allow casts from numeric types to floats
    
    Fixes Rust-GCC#3261
    
    gcc/rust/ChangeLog:
    
            * typecheck/rust-casts.cc (TypeCastRules::cast_rules): allow casts 
to float
    
    gcc/testsuite/ChangeLog:
    
            * rust/compile/issue-3261.rs: New test.
    
    Signed-off-by: Philip Herron <herron.phi...@googlemail.com>

Diff:
---
 gcc/rust/typecheck/rust-casts.cc         | 10 ++++++++++
 gcc/testsuite/rust/compile/issue-3261.rs | 18 ++++++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/gcc/rust/typecheck/rust-casts.cc b/gcc/rust/typecheck/rust-casts.cc
index 87b31b5820f6..fb7951032491 100644
--- a/gcc/rust/typecheck/rust-casts.cc
+++ b/gcc/rust/typecheck/rust-casts.cc
@@ -200,6 +200,16 @@ TypeCastRules::cast_rules ()
          }
          break;
 
+         case TyTy::TypeKind::FLOAT: {
+           // can only do this for number types not char
+           bool from_char
+             = from.get_ty ()->get_kind () == TyTy::TypeKind::CHAR;
+           if (!from_char)
+             return TypeCoercionRules::CoercionResult{{},
+                                                      to.get_ty ()->clone ()};
+         }
+         break;
+
        case TyTy::TypeKind::INFER:
        case TyTy::TypeKind::USIZE:
        case TyTy::TypeKind::ISIZE:
diff --git a/gcc/testsuite/rust/compile/issue-3261.rs 
b/gcc/testsuite/rust/compile/issue-3261.rs
new file mode 100644
index 000000000000..37e974d61696
--- /dev/null
+++ b/gcc/testsuite/rust/compile/issue-3261.rs
@@ -0,0 +1,18 @@
+// { dg-options "-w" }
+fn main() {
+    let a: i8 = 50;
+    let b = a as f32;
+    let c = a as f64;
+
+    let a: i16 = 1337;
+    let b = a as f32;
+    let c = a as f64;
+
+    let a: i32 = 1337;
+    let b = a as f32;
+    let c = a as f64;
+
+    let a: i64 = 1337;
+    let b = a as f32;
+    let c = a as f64;
+}