[PATCH] arm.c: Clarify error message in thumb1_expand_prologue

[Christophe Lyon via Gcc-patches]

While running the tests with -march=armv5t -mthumb, I came across this
error message which I think could be clearer.

2020-05-14  Christophe Lyon  <christophe.l...@linaro.org>

        gcc/
        * config/arm/arm.c (thumb1_expand_prologue): Update error message.
---
 gcc/config/arm/arm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index d507819..dda8771 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -26502,7 +26502,7 @@ thumb1_expand_prologue (void)
 
   if (IS_INTERRUPT (func_type))
     {
-      error ("interrupt Service Routines cannot be coded in Thumb mode");
+      error ("Interrupt Service Routines cannot be coded in Thumb-1 mode");
       return;
     }
 
-- 
2.7.4