Expose RTS-only ways (#18651)

Some RTS ways are exposed via settings (ghcThreaded, ghcDebugged) but
not all. It's simpler if the RTS exposes them all itself.

1 files changed, 33 insertions, 0 deletions

diff --git a/rts/RtsUtils.c b/rts/RtsUtils.c
index e88babcd08..ca01bdb6e0 100644
--- a/rts/RtsUtils.c
+++ b/rts/RtsUtils.c
@@ -363,6 +363,39 @@ int rts_isDynamic(void)
 #endif
 }
 
+// Provides a way for Haskell programs to tell whether they're
+// linked with the threaded runtime or not.
+int rts_isThreaded(void)
+{
+#if defined(THREADED_RTS)
+    return 1;
+#else
+    return 0;
+#endif
+}
+
+// Provides a way for Haskell programs to tell whether they're
+// linked with the debug runtime or not.
+int rts_isDebugged(void)
+{
+#if defined(DEBUG)
+    return 1;
+#else
+    return 0;
+#endif
+}
+
+// Provides a way for Haskell programs to tell whether they're
+// linked with the tracing runtime or not.
+int rts_isTracing(void)
+{
+#if defined(TRACING)
+    return 1;
+#else
+    return 0;
+#endif
+}
+
 // Used for detecting a non-empty FPU stack on x86 (see #4914)
 void checkFPUStack(void)
 {