From d87f9ae5a974aaff525202b0d65b1cd3ec4a7475 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dag=20Br=C3=BCck?= <dag.bruck@3ds.com>
Date: Wed, 29 Apr 2026 08:31:33 +0200
Subject: [PATCH 1/2] Initialize pointer variables to NULL in
 ModelicaInternal.c

Pointer variables initialized at definition.
---
 .../Resources/C-Sources/ModelicaInternal.c    | 30 +++++++++----------
 1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/Modelica/Resources/C-Sources/ModelicaInternal.c b/Modelica/Resources/C-Sources/ModelicaInternal.c
index bd2d2ae68e..61d8e4a820 100644
--- a/Modelica/Resources/C-Sources/ModelicaInternal.c
+++ b/Modelica/Resources/C-Sources/ModelicaInternal.c
@@ -755,7 +755,7 @@ _Ret_z_ const char* ModelicaInternal_fullPathName(_In_z_ const char* name) {
 
 _Ret_z_ const char* ModelicaInternal_temporaryFileName(void) {
     /* Get full path name of a temporary file name which does not exist */
-    char* fullName;
+    char* fullName = NULL;
 
     char* tempName = tmpnam(NULL);
     if (tempName == NULL) {
@@ -834,7 +834,7 @@ static void G2_FUNCNAME(ModelicaInternal_deleteCS)(void) {
 #endif
 
 static void CacheFileForReading(FILE* fp, const char* fileName, int lineNumber, char* buf, int bufLen) {
-    FileCache* fv;
+    FileCache* fv = NULL;
     size_t len;
     if (fileName == NULL) {
         /* Do not add, close file */
@@ -878,7 +878,7 @@ static void CacheFileForReading(FILE* fp, const char* fileName, int lineNumber,
 }
 
 static void CloseCachedFile(const char* fileName) {
-    FileCache* fv;
+    FileCache* fv = NULL;
     size_t len = strlen(fileName);
     MUTEX_LOCK();
     HASH_FIND(hh, fileCache, fileName, (unsigned)len, fv);
@@ -896,8 +896,8 @@ static void CloseCachedFile(const char* fileName) {
 
 static FILE* ModelicaStreams_openFileForReading(const char* fileName, int lineNumber, int* lineNumberOffset, char** buf, int* bufLen) {
     /* Open text file for reading */
-    FILE* fp;
-    FileCache* fv;
+    FILE* fp = NULL;
+    FileCache* fv = NULL;
     size_t len = strlen(fileName);
     *lineNumberOffset = 0;
     *buf = NULL;
@@ -954,7 +954,7 @@ void ModelicaStreams_closeFile(_In_z_ const char* fileName) {
 
 static FILE* ModelicaStreams_openFileForWriting(const char* fileName) {
     /* Open text file for writing (with append) */
-    FILE* fp;
+    FILE* fp = NULL;
 
     /* Check fileName */
     if ( fileName[0] == '\0' ) {
@@ -973,8 +973,8 @@ static FILE* ModelicaStreams_openFileForWriting(const char* fileName) {
 }
 
 static int readLine(_In_ char** buf, _In_ int* bufLen, _In_ FILE* fp) {
-    char* offset;
-    int oldBufLen;
+    char* offset = NULL;
+    int oldBufLen = 0;
 
     if (fgets(*buf, *bufLen, fp) == NULL) {
         return EOF;
@@ -1041,7 +1041,7 @@ int ModelicaInternal_countLines(_In_z_ const char* fileName) {
     /* Get number of lines of a file */
     int lineNumberOffset;
     int bufLen;
-    char* buf;
+    char* buf = NULL;
     int c;
     int nLines = 0;
     int start_of_line = 1;
@@ -1068,9 +1068,9 @@ void ModelicaInternal_readFile(_In_z_ const char* fileName,
     /* Read file into string vector string[nLines] */
     int lineNumberOffset;
     int bufLen;
-    char* buf;
+    char* buf = NULL;
     FILE* fp = ModelicaStreams_openFileForReading(fileName, 0, &lineNumberOffset, &buf, &bufLen);
-    char* line;
+    char* line = NULL;
     size_t iLines = 1;
 
     if (buf == NULL) {
@@ -1184,8 +1184,8 @@ void ModelicaInternal_chdir(_In_z_ const char* directoryName) {
 }
 
 _Ret_z_ const char* ModelicaInternal_getcwd(int dummy) {
-    const char* cwd;
-    char* directory;
+    const char* cwd = NULL;
+    char* directory = NULL;
 
 #if defined(__WATCOMC__) || defined(__BORLANDC__) || defined(_POSIX_) || defined(__GNUC__)
     char localbuf[BUFFER_LENGTH];
@@ -1212,9 +1212,9 @@ _Ret_z_ const char* ModelicaInternal_getcwd(int dummy) {
 void ModelicaInternal_getenv(_In_z_ const char* name, int convertToSlash,
                              _Out_ const char** content, _Out_ int* exist) {
     /* Get content of environment variable */
-    char* result;
+    char* result = NULL;
 #if defined(_MSC_VER) && _MSC_VER >= 1400
-    char* value;
+    char* value = NULL;
     size_t len = 0;
     errno_t err = _dupenv_s(&value, &len, name);
     if (err) {

From 9ac5e0944f10b83ecbfa7ec8cfe4df790f2689c6 Mon Sep 17 00:00:00 2001
From: StephanZiegler <Stephan.Ziegler@3ds.com>
Date: Wed, 29 Apr 2026 10:08:12 +0200
Subject: [PATCH 2/2] added changelog entry

---
 Modelica/Resources/C-Sources/ModelicaInternal.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Modelica/Resources/C-Sources/ModelicaInternal.c b/Modelica/Resources/C-Sources/ModelicaInternal.c
index 61d8e4a820..3e68aeea0f 100644
--- a/Modelica/Resources/C-Sources/ModelicaInternal.c
+++ b/Modelica/Resources/C-Sources/ModelicaInternal.c
@@ -30,6 +30,9 @@
 */
 
 /* Changelog:
+      Apr. 29, 2026: by Dag Brueck, Dassault Systemes AB
+                     Initialize pointer variables to NULL
+                     (ticket #4783)
       Oct. 20, 2024: by Thomas Beutlich
                      Removed legacy behaviour in ModelicaInternal_stat for
                      MSVC Visual Studio >= 2015 (ticket #4473)