From e96da30ac7f50639954d242cf7fb35100645f0e6 Mon Sep 17 00:00:00 2001
From: Herman Semenoff <GermanAizek@yandex.ru>
Date: Fri, 31 Jul 2026 16:29:51 +0300
Subject: [PATCH] asm: nasmlib: remove excess checks before free()

More info: https://stackoverflow.com/questions/13818803/check-for-null-before-delete-in-c-good-practice

In C this became possible after C89, code is cleaner.

```
 C89: 4.10.3.2 The free function.

The free function causes the space pointed to by ptr to be deallocated, that is, made available for further allocation. If ptr is a null pointer, no action occurs.
```
---
 asm/assemble.c    | 3 +--
 asm/labels.c      | 6 ++----
 asm/parser.c      | 3 +--
 asm/preproc.c     | 1 -
 nasmlib/alloc.c   | 6 ++----
 nasmlib/hashtbl.c | 3 +--
 6 files changed, 7 insertions(+), 15 deletions(-)

diff --git a/asm/assemble.c b/asm/assemble.c
index 023aa3bf0..68aaac499 100644
--- a/asm/assemble.c
+++ b/asm/assemble.c
@@ -1016,8 +1016,7 @@ static int64_t assemble(insn *instruction)
                           " reading file `%s'", fname);
         }
     close_done:
-        if (buf)
-            nasm_free(buf);
+        nasm_free(buf);
         if (map)
             nasm_unmap_file(map, len);
         fclose(fp);
diff --git a/asm/labels.c b/asm/labels.c
index 9a5fd5d25..06ad56270 100644
--- a/asm/labels.c
+++ b/asm/labels.c
@@ -210,8 +210,7 @@ static union label *find_label(const char *label, bool create, bool *created)
     if (lptr || !create) {
         if (created)
             *created = false;
-        if (label_str)
-            nasm_free(label_str);
+        nasm_free(label_str);
 
         return lptr;
     }
@@ -232,8 +231,7 @@ static union label *find_label(const char *label, bool create, bool *created)
     nasm_zero(*lfree);
     lfree->defn.label     = perm_copy(label);
     lfree->defn.subsection = NO_SEG;
-    if (label_str)
-        nasm_free(label_str);
+    nasm_free(label_str);
 
     hash_add(&ip, lfree->defn.label, lfree);
     return lfree++;
diff --git a/asm/parser.c b/asm/parser.c
index b8ceed827..3e242c033 100644
--- a/asm/parser.c
+++ b/asm/parser.c
@@ -618,8 +618,7 @@ static int parse_eops(extop **result, bool critical, int elem)
     return oper_num;
 
 fail:
-    if (eop)
-        nasm_free(eop);
+    nasm_free(eop);
     return -1;
 }
 
diff --git a/asm/preproc.c b/asm/preproc.c
index eebb1238a..f076f5f7a 100644
--- a/asm/preproc.c
+++ b/asm/preproc.c
@@ -950,7 +950,6 @@ static const char *pp_getenv(const Token *t, bool warn)
 	v = "";
     }
 
-    if (buf)
 	nasm_free(buf);
 
     return v;
diff --git a/nasmlib/alloc.c b/nasmlib/alloc.c
index 71570a33b..8608953d9 100644
--- a/nasmlib/alloc.c
+++ b/nasmlib/alloc.c
@@ -74,8 +74,7 @@ void *nasm_realloc(void *q, size_t size)
 
 void nasm_free(void *q)
 {
-    if (q)
-        free(q);
+    free(q);
 }
 
 char *nasm_strdup(const char *s)
@@ -103,8 +102,7 @@ char *nasm_strdupto(char **ptrp, const char *str)
 {
     char *ptr = *ptrp;
     if (str) {
-        if (ptr)
-            nasm_free(ptr);
+        nasm_free(ptr);
         *ptrp = ptr = nasm_strdup(str);
     }
     return ptr;
diff --git a/nasmlib/hashtbl.c b/nasmlib/hashtbl.c
index 5faba36b6..9651d3710 100644
--- a/nasmlib/hashtbl.c
+++ b/nasmlib/hashtbl.c
@@ -251,8 +251,7 @@ void hash_free_all(struct hash_table *head, bool free_keys)
     const struct hash_node *np;
 
     hash_for_each(head, it, np) {
-        if (np->data)
-            nasm_free(np->data);
+        nasm_free(np->data);
         if (free_keys && np->key)
             nasm_free((void *)np->key);
     }