Fix return value for memset

Makefile

@@ -20,13 +20,13 @@ bldtst: buildtest.c arch/*.c
 	gcc -static -nostdlib -Wno-builtin-declaration-mismatch -fno-stack-protector -o bldtst buildtest.c arch/*.c
 
 bldtst_llvm: buildtest.c arch/*.c
-	clang -nostdlib -static -fuse-ld=lld -fno-stack-protector -o bldtst_llvm buildtest.c arch/*.c
+	clang -nostdlib -Wno-incompatible-library-redeclaration -static -fuse-ld=lld -fno-stack-protector -o bldtst_llvm buildtest.c arch/*.c
 
 bldtst_x64: buildtest.c arch/x86_64.c
-	clang --target=x86_64-linux-gnu -nostdlib -static -fuse-ld=lld -fno-stack-protector -o bldtst_x64 buildtest.c arch/x86_64.c
+	clang --target=x86_64-linux-gnu -nostdlib -Wno-incompatible-library-redeclaration -static -fuse-ld=lld -fno-stack-protector -o bldtst_x64 buildtest.c arch/x86_64.c
 
 bldtst_aarch64: buildtest.c
-	clang --target=aarch64-linux-gnu -nostdlib -static -fuse-ld=lld -fno-stack-protector -o bldtst_aarch64 buildtest.c arch/aarch64.c
+	clang --target=aarch64-linux-gnu -nostdlib -Wno-incompatible-library-redeclaration -static -fuse-ld=lld -fno-stack-protector -o bldtst_aarch64 buildtest.c arch/aarch64.c
 
 bldtst_mips32: buildtest.c
-	clang --target=mips-linux-gnu -nostdlib -static -fuse-ld=lld -fno-stack-protector -fno-pic -o bldtst_mips32 buildtest.c arch/mips.c
+	clang --target=mips-linux-gnu -nostdlib -Wno-incompatible-library-redeclaration -static -fuse-ld=lld -fno-stack-protector -fno-pic -o bldtst_mips32 buildtest.c arch/mips.c

arch/aarch64.c

@@ -9,6 +9,7 @@ void exit(int8_t status){
         : "r" ((long)status)         // Input operand: status
         : "x0", "x8"           // Clobbered registers
   );
+  for (;;);
 }
 
 intptr_t write(int32_t fd, const void* buf, intptr_t size){

arch/mips.c

@@ -10,6 +10,7 @@ void exit(int8_t status){
     : "r" (status)
     : "a0", "v0"
   );
+  for(;;);
 }
 
 intptr_t write(int32_t fd, const void* buf, intptr_t size){

arch/x86_64.c

@@ -9,6 +9,7 @@ void exit(int8_t status) {
     : "a"(SYS_EXIT), "D"(status)
     :
   );
+  for(;;);
 }
 
 #define SYS_WRITE 1

sys.h

@@ -16,5 +16,6 @@ uint32_t fork();
 void *memset(void* s, int c, unsigned long n) {
   int8_t* mem = s;
   for(long int i = 0; i < n; ++i) mem[i] = c;
+  return s;
 }
 #endif // !MINIMALSYS_H