[flang-commits] [flang] aea94c9 - [flang] Adjust checks of ICHAR/IACHAR argument length (#72312)

[via flang-commits]

Author: Peter Klausler
Date: 2023-11-30T11:15:34-08:00
New Revision: aea94c90b39b2694f3a1b2f23f06f005c9d3459b

URL: https://github.com/llvm/llvm-project/commit/aea94c90b39b2694f3a1b2f23f06f005c9d3459b
DIFF: https://github.com/llvm/llvm-project/commit/aea94c90b39b2694f3a1b2f23f06f005c9d3459b.diff

LOG: [flang] Adjust checks of ICHAR/IACHAR argument length (#72312)

The compiler will now emit an error for length == 0 and an
off-by-default portability warning for length > 1. Previously, the
message was an unconditional warning for length /= 1.

Added: 
    flang/test/Semantics/ichar01.f90

Modified: 
    flang/lib/Evaluate/fold-integer.cpp

Removed: 
    


################################################################################
diff  --git a/flang/lib/Evaluate/fold-integer.cpp b/flang/lib/Evaluate/fold-integer.cpp
index 2882369105f6626..c60648fb195f22e 100644
--- a/flang/lib/Evaluate/fold-integer.cpp
+++ b/flang/lib/Evaluate/fold-integer.cpp
@@ -677,10 +677,16 @@ Expr<Type<TypeCategory::Integer, KIND>> FoldIntrinsicFunction(
     auto *someChar{UnwrapExpr<Expr<SomeCharacter>>(args[0])};
     CHECK(someChar);
     if (auto len{ToInt64(someChar->LEN())}) {
-      if (len.value() != 1) {
+      if (len.value() < 1) {
+        context.messages().Say(
+            "Character in intrinsic function %s must have length one"_err_en_US,
+            name);
+      } else if (len.value() > 1 &&
+          context.languageFeatures().ShouldWarn(
+              common::UsageWarning::Portability)) {
         // Do not die, this was not checked before
         context.messages().Say(
-            "Character in intrinsic function %s must have length one"_warn_en_US,
+            "Character in intrinsic function %s should have length one"_port_en_US,
             name);
       } else {
         return common::visit(

diff  --git a/flang/test/Semantics/ichar01.f90 b/flang/test/Semantics/ichar01.f90
new file mode 100644
index 000000000000000..5eb25a97e6d939e
--- /dev/null
+++ b/flang/test/Semantics/ichar01.f90
@@ -0,0 +1,13 @@
+! RUN: %python %S/test_errors.py %s %flang_fc1 -pedantic
+!ERROR: Character in intrinsic function ichar must have length one
+print *, ichar('')
+!ERROR: Character in intrinsic function iachar must have length one
+print *, iachar('')
+print *, ichar('a')
+print *, iachar('a')
+!PORTABILITY: Character in intrinsic function ichar should have length one
+print *, ichar('ab')
+!PORTABILITY: Character in intrinsic function iachar should have length one
+print *, iachar('ab')
+end
+