[flang-commits] [flang] [flang] Fix const cast issue in FreeMemory function call in execute_command_line (PR #77906)

[Yi Wu via flang-commits]

https://github.com/yi-wu-arm updated https://github.com/llvm/llvm-project/pull/77906

>From 2a36ab7f05771662c361a301f02039757694151a Mon Sep 17 00:00:00 2001
From: Yi Wu <yi.wu2 at arm.com>
Date: Fri, 12 Jan 2024 11:01:06 +0000
Subject: [PATCH 1/2] Fix const cast issue in FreeMemory function call

The FreeMemory function only accepts a void pointer,
but it was being called with a const char pointer,
resulting in a type-casting issue.
To address this, the commit replaces the direct cast with a
const_cast<void *>(static_cast<const void *>(newCmd).
---
 flang/runtime/execute.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/flang/runtime/execute.cpp b/flang/runtime/execute.cpp
index 48773ae8114b0b..fa2b7eca0dde69 100644
--- a/flang/runtime/execute.cpp
+++ b/flang/runtime/execute.cpp
@@ -199,7 +199,7 @@ void RTNAME(ExecuteCommandLine)(const Descriptor &command, bool wait,
   }
   // Deallocate memory if EnsureNullTerminated dynamically allocated memory
   if (newCmd != command.OffsetElement()) {
-    FreeMemory((void *)newCmd);
+    FreeMemory(const_cast<void *>(static_cast<const void *>(newCmd)));
   }
 }
 

>From 0525df1ba81764c10c6f0f4ab1d7a6d616430c6a Mon Sep 17 00:00:00 2001
From: Yi Wu <yi.wu2 at arm.com>
Date: Fri, 12 Jan 2024 13:40:43 +0000
Subject: [PATCH 2/2] remove const

---
 flang/runtime/execute.cpp | 4 ++--
 flang/runtime/tools.cpp   | 4 ++--
 flang/runtime/tools.h     | 4 ++--
 3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/flang/runtime/execute.cpp b/flang/runtime/execute.cpp
index fa2b7eca0dde69..3a818670c96452 100644
--- a/flang/runtime/execute.cpp
+++ b/flang/runtime/execute.cpp
@@ -116,7 +116,7 @@ void RTNAME(ExecuteCommandLine)(const Descriptor &command, bool wait,
     const Descriptor *exitstat, const Descriptor *cmdstat,
     const Descriptor *cmdmsg, const char *sourceFile, int line) {
   Terminator terminator{sourceFile, line};
-  const char *newCmd{EnsureNullTerminated(
+  char *newCmd{EnsureNullTerminated(
       command.OffsetElement(), command.ElementBytes(), terminator)};
 
   if (exitstat) {
@@ -199,7 +199,7 @@ void RTNAME(ExecuteCommandLine)(const Descriptor &command, bool wait,
   }
   // Deallocate memory if EnsureNullTerminated dynamically allocated memory
   if (newCmd != command.OffsetElement()) {
-    FreeMemory(const_cast<void *>(static_cast<const void *>(newCmd)));
+    FreeMemory((void *)newCmd);
   }
 }
 
diff --git a/flang/runtime/tools.cpp b/flang/runtime/tools.cpp
index 6d2d86586c5fe6..e653323ed1de03 100644
--- a/flang/runtime/tools.cpp
+++ b/flang/runtime/tools.cpp
@@ -173,8 +173,8 @@ RT_API_ATTRS void ShallowCopy(const Descriptor &to, const Descriptor &from) {
   ShallowCopy(to, from, to.IsContiguous(), from.IsContiguous());
 }
 
-RT_API_ATTRS const char *EnsureNullTerminated(
-    const char *str, std::size_t length, Terminator &terminator) {
+RT_API_ATTRS char *EnsureNullTerminated(
+    char *str, std::size_t length, Terminator &terminator) {
   if (std::memchr(str, '\0', length) == nullptr) {
     char *newCmd{(char *)AllocateMemoryOrCrash(terminator, length + 1)};
     std::memcpy(newCmd, str, length);
diff --git a/flang/runtime/tools.h b/flang/runtime/tools.h
index 47398a910ce73d..89e5069995748b 100644
--- a/flang/runtime/tools.h
+++ b/flang/runtime/tools.h
@@ -441,8 +441,8 @@ RT_API_ATTRS void ShallowCopy(const Descriptor &to, const Descriptor &from);
 // size memory for null-terminator if necessary. Returns the original or a newly
 // allocated null-terminated string (responsibility for deallocation is on the
 // caller).
-RT_API_ATTRS const char *EnsureNullTerminated(
-    const char *str, std::size_t length, Terminator &terminator);
+RT_API_ATTRS char *EnsureNullTerminated(
+    char *str, std::size_t length, Terminator &terminator);
 
 RT_API_ATTRS bool IsValidCharDescriptor(const Descriptor *value);