[flang-commits] [flang] [FLANG] Fix for issue #127426 (PR #150008)

[Aadesh Premkumar via flang-commits]

https://github.com/aadeshps-mcw created https://github.com/llvm/llvm-project/pull/150008

None

>From adf5b62e464eab1eb2834138bd0ddf4276738963 Mon Sep 17 00:00:00 2001
From: Aadesh PremKumar <aadesh.premkumar at multicorewareinc.com>
Date: Tue, 22 Jul 2025 17:51:01 +0530
Subject: [PATCH] --Fix for issue #127426

---
 flang/lib/Parser/prescan.cpp |  7 ++++---
 flang/test/Parser/inc.h      |  4 ++++
 flang/test/Parser/test.F     | 14 ++++++++++++++
 3 files changed, 22 insertions(+), 3 deletions(-)
 create mode 100644 flang/test/Parser/inc.h
 create mode 100644 flang/test/Parser/test.F

diff --git a/flang/lib/Parser/prescan.cpp b/flang/lib/Parser/prescan.cpp
index 3a9a475c365ee..06c9456b203a9 100644
--- a/flang/lib/Parser/prescan.cpp
+++ b/flang/lib/Parser/prescan.cpp
@@ -175,7 +175,7 @@ void Prescanner::Statement() {
       EmitChar(tokens, '!');
       ++at_, ++column_;
       for (const char *sp{directiveSentinel_}; *sp != '\0';
-           ++sp, ++at_, ++column_) {
+          ++sp, ++at_, ++column_) {
         EmitChar(tokens, *sp);
       }
       if (inFixedForm_) {
@@ -435,6 +435,7 @@ void Prescanner::LabelField(TokenSequence &token) {
   int outCol{1};
   const char *start{at_};
   std::optional<int> badColumn;
+  SkipCComments();
   for (; *at_ != '\n' && column_ <= 6; ++at_) {
     if (*at_ == '\t') {
       ++at_;
@@ -1218,7 +1219,7 @@ std::optional<std::size_t> Prescanner::IsIncludeLine(const char *start) const {
   }
   if (IsDecimalDigit(*p)) { // accept & ignore a numeric kind prefix
     for (p = SkipWhiteSpace(p + 1); IsDecimalDigit(*p);
-         p = SkipWhiteSpace(p + 1)) {
+        p = SkipWhiteSpace(p + 1)) {
     }
     if (*p != '_') {
       return std::nullopt;
@@ -1266,7 +1267,7 @@ void Prescanner::FortranInclude(const char *firstQuote) {
   llvm::raw_string_ostream error{buf};
   Provenance provenance{GetProvenance(nextLine_)};
   std::optional<std::string> prependPath;
-  if (const SourceFile * currentFile{allSources_.GetSourceFile(provenance)}) {
+  if (const SourceFile *currentFile{allSources_.GetSourceFile(provenance)}) {
     prependPath = DirectoryName(currentFile->path());
   }
   const SourceFile *included{
diff --git a/flang/test/Parser/inc.h b/flang/test/Parser/inc.h
new file mode 100644
index 0000000000000..1e31cb035ccf1
--- /dev/null
+++ b/flang/test/Parser/inc.h
@@ -0,0 +1,4 @@
+/* Old-style C comments
+ * Comments
+ */
+#define VAL 1
diff --git a/flang/test/Parser/test.F b/flang/test/Parser/test.F
new file mode 100644
index 0000000000000..c482bc0023b66
--- /dev/null
+++ b/flang/test/Parser/test.F
@@ -0,0 +1,14 @@
+! RUN: %flang_fc1 -fdebug-unparse-no-sema %s 2>&1 | FileCheck %s
+
+! CHECK: SUBROUTINE foo
+! CHECK: INTEGER i
+! CHECK: i = 1
+! CHECK: PRINT *, i
+! CHECK: END SUBROUTINE foo
+
+subroutine foo()
+#include "inc.h"
+  integer :: i
+  i = VAL
+  print *, i
+end subroutine foo