Fix crash during emitCast of attributed type, allow MaxIters to take linktime const. (#5791)

* Fix crash during emitCast of attributed type.

* Allow [MaxIters] to take link time constants.

---------

Co-authored-by: Ellie Hermaszewska <ellieh@nvidia.com>

1 files changed, 15 insertions, 0 deletions

diff --git a/tests/language-feature/constants/max-iters-link-time-const.slang b/tests/language-feature/constants/max-iters-link-time-const.slang
new file mode 100644
index 000000000..cf1ccbbd1
--- /dev/null
+++ b/tests/language-feature/constants/max-iters-link-time-const.slang
@@ -0,0 +1,15 @@
+//TEST:SIMPLE(filecheck=CHECK): -target spirv
+// CHECK: OpEntryPoint
+
+extern static const int num = 10;
+RWStructuredBuffer<float> outputBuffer;
+
+[numthreads(1,1,1)]
+void computeMain()
+{
+    [MaxIters(num)]
+    for (int i = 0; i < num; i++)
+    {
+        outputBuffer[i] = i;
+    }
+}