What is the meaning of "Invalid argument" from qemu? (cortex-m-quickstart)

[tgross35]

I'm just having no luck with cross compilation today. I'm trying to run the cortex-m-quickstart package by cloning the repo, then applying this patch (to fix project names and set cross target)

diff --git a/Cargo.toml b/Cargo.toml
index 8cf925a..cc793c0 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -2,7 +2,7 @@
 authors = ["{{authors}}"]
 edition = "2018"
 readme = "README.md"
-name = "{{project-name}}"
+name = "myproject"
 version = "0.1.0"
 
 [dependencies]
@@ -11,6 +11,10 @@ cortex-m-rt = "0.6.10"
 cortex-m-semihosting = "0.3.3"
 panic-halt = "0.2.0"
 
+[package.metadata.cross.build]
+#default-target = "thumbv7em-none-eabihf"
+default-target = "thumbv7m-none-eabi"
+
 # Uncomment for the panic example.
 # panic-itm = "0.4.1"
 
@@ -26,7 +30,7 @@ panic-halt = "0.2.0"
 
 # this lets you use `cargo fix`!
 [[bin]]
-name = "{{project-name}}"
+name = "myproject"
 test = false
 bench = false

It builds fine and doesn't seem to hit any of the issues in the Cross readme, but I always get the following result when trying to run:

$ cross run
...
    Finished dev [unoptimized + debuginfo] target(s) in 5.01s
     Running `qemu-arm /target/thumbv7m-none-eabi/debug/myproj`
/target/thumbv7m-none-eabi/debug/myproj: Invalid argument

It seems like it would be simple, what am I missing?

(Once I figure this out, I'll open a docs PR on the cortex-m-quickstart crate for how to build it with cross)