[flang-commits] [flang] [flang] Check for errors when analyzing array constructors (PR #173092)

[Leandro Lupori via flang-commits]

https://github.com/luporl created https://github.com/llvm/llvm-project/pull/173092

Errors in array constructor values result in the array having
less elements than it should, which can cause other errors that
will confuse the user. Avoid this by not returning an expression
on errors.

Fixes #127425


>From d57f922c21f5034bbe3d3bc4624b8d86abd8356c Mon Sep 17 00:00:00 2001
From: Leandro Lupori <leandro.lupori at linaro.org>
Date: Fri, 19 Dec 2025 16:27:02 -0300
Subject: [PATCH] [flang] Check for errors when analyzing array constructors

Errors in array constructor values result in the array having
less elements than it should, which can cause other errors that
will confuse the user. Avoid this by not returning an expression
on errors.

Fixes #127425
---
 flang/lib/Semantics/expression.cpp | 4 ++++
 flang/test/Semantics/bug127425.f90 | 8 ++++++++
 2 files changed, 12 insertions(+)
 create mode 100644 flang/test/Semantics/bug127425.f90

diff --git a/flang/lib/Semantics/expression.cpp b/flang/lib/Semantics/expression.cpp
index 6f5d0bf9eb242..0b67d1ae013a2 100644
--- a/flang/lib/Semantics/expression.cpp
+++ b/flang/lib/Semantics/expression.cpp
@@ -2076,11 +2076,15 @@ MaybeExpr ArrayConstructorContext::ToExpr() {
 
 MaybeExpr ExpressionAnalyzer::Analyze(const parser::ArrayConstructor &array) {
   const parser::AcSpec &acSpec{array.v};
+  bool hadAnyFatalError{context_.AnyFatalError()};
   ArrayConstructorContext acContext{
       *this, AnalyzeTypeSpec(acSpec.type, GetFoldingContext())};
   for (const parser::AcValue &value : acSpec.values) {
     acContext.Add(value);
   }
+  if (!hadAnyFatalError && context_.AnyFatalError()) {
+    return std::nullopt;
+  }
   return acContext.ToExpr();
 }
 
diff --git a/flang/test/Semantics/bug127425.f90 b/flang/test/Semantics/bug127425.f90
new file mode 100644
index 0000000000000..b01fabba70135
--- /dev/null
+++ b/flang/test/Semantics/bug127425.f90
@@ -0,0 +1,8 @@
+! RUN: %python %S/test_errors.py %s %flang_fc1
+
+program main
+  pointer (j1,ja)
+  pointer (j2,jb)
+  !ERROR: Values in array constructor must have the same declared type when no explicit type appears
+  if (any((/j1,j2,j3,j4,j5/)/=(/1,2,3,4,5/))) print *,'fail'
+end program main