kos-crt-stub: Minimal implementation added

Signed-off-by: Maxim Logaev <maxlogaev@proton.me>

build-toolchain.sh

@@ -11,6 +11,7 @@ PATH=$PATH:"$SDK_TOOLCHAIN_DIR/bin"
 declare -a DIRS=(
     "toolchain/binutils"
     "toolchain/gcc"
+    "libraries/kos-crt-stub"
 )
 
 BUILD()

libraries/kos-crt-stub/crt-stub.c

@@ -0,0 +1,13 @@
+extern int main (void);
+
+__attribute__((noreturn)) void _crt_start(void)
+{
+    main();
+    __asm__("int $0x40" ::"a"(-1));
+    __builtin_unreachable();
+}
+
+int atexit(void (*func)( void ))
+{
+    return 1;
+}

libraries/kos-crt-stub/kos-app.lds

@@ -0,0 +1,118 @@
+ENTRY(__crt_start)
+SECTIONS
+{
+    .text 0x0:
+    {
+        LONG(0x554e454D);
+        LONG(0x32305445);
+        LONG(1);
+        LONG(__crt_start);
+        LONG(___iend);
+        LONG(___memsize);
+        LONG(___stacktop);
+        LONG(___cmdline);
+        LONG(___pgmname);     /* full path */
+        LONG(__subsystem__);
+
+        *(.init)
+        *(.text)
+        *(SORT(.text$*))
+        *(.text.*)
+        *(.glue_7t)
+        *(.glue_7)
+
+        ___CTOR_LIST__ = .; __CTOR_LIST__ = . ;
+                        LONG (-1);*(.ctors); *(.ctor); *(SORT(.ctors.*));  LONG (0);
+        ___DTOR_LIST__ = .; __DTOR_LIST__ = . ;
+                        LONG (-1); *(.dtors); *(.dtor); *(SORT(.dtors.*));  LONG (0);
+        *(.fini)
+        /* ??? Why is .gcc_exc here? */
+        *(.gcc_exc)
+        PROVIDE (etext = .);
+        *(.gcc_except_table)
+    }
+
+    .rdata ALIGN(16) :
+    {
+        *(.rdata)
+        *(SORT(.rdata$*))
+        ___RUNTIME_PSEUDO_RELOC_LIST__ = .;
+        __RUNTIME_PSEUDO_RELOC_LIST__ = .;
+        *(.rdata_runtime_pseudo_reloc)
+        ___RUNTIME_PSEUDO_RELOC_LIST_END__ = .;
+        __RUNTIME_PSEUDO_RELOC_LIST_END__ = .;
+    }
+
+    .CRT ALIGN(16) :
+    {
+         ___crt_xc_start__ = . ;
+        *(SORT(.CRT$XC*))  /* C initialization */
+        ___crt_xc_end__ = . ;
+        ___crt_xi_start__ = . ;
+        *(SORT(.CRT$XI*))  /* C++ initialization */
+        ___crt_xi_end__ = . ;
+        ___crt_xl_start__ = . ;
+        *(SORT(.CRT$XL*))  /* TLS callbacks */
+        /* ___crt_xl_end__ is defined in the TLS Directory support code */
+        ___crt_xp_start__ = . ;
+        *(SORT(.CRT$XP*))  /* Pre-termination */
+        ___crt_xp_end__ = . ;
+        ___crt_xt_start__ = . ;
+        *(SORT(.CRT$XT*))  /* Termination */
+        ___crt_xt_end__ = . ;
+    }
+
+    .data ALIGN(16) :
+    {
+        PROVIDE ( __data_start__ = .) ;
+        *(.data)
+        *(.data2)
+        *(SORT(.data$*))
+        *(.jcr)
+        __CRT_MT = .;
+        LONG(1);
+        PROVIDE ( __data_end__ = .) ;
+        *(.data_cygwin_nocopy)
+        ___iend = . ;
+    }
+
+    .eh_frame BLOCK(16) :
+    {
+        PROVIDE (___EH_FRAME_BEGIN__ = .) ;
+        *(.eh_frame*)
+        ___FRAME_END__ = . ;
+        LONG(0);
+    }
+
+    .bss ALIGN(16):
+    {
+        *(.bss)
+        *(COMMON)
+        . = ALIGN(16);
+        ___cmdline = .;
+        . = . + 256;
+        ___pgmname = .;
+        . = . + 1024 + 16;
+        ___stacktop = .;
+        ___memsize = . ;
+    }
+
+    /DISCARD/ :
+    {
+        *(.debug$S)
+        *(.debug$T)
+        *(.debug$F)
+        *(.drectve)
+        *(.note.GNU-stack)
+        *(.comment)
+        *(.debug_abbrev)
+        *(.debug_info)
+        *(.debug_line)
+        *(.debug_frame)
+        *(.debug_loc)
+        *(.debug_pubnames)
+        *(.debug_aranges)
+        *(.debug_ranges)
+        *(.reloc)
+    }
+}

libraries/kos-crt-stub/kos-recipe.sh

@@ -0,0 +1,26 @@
+#!/bin/bash
+
+# Copyright (C) KolibriOS-NG team 2024. All rights reserved
+# Distributed under terms of the GNU General Public License
+
+source ../../scripts/start-recipe
+
+BUILD()
+{
+    i586-kolibrios-gcc -c crt-stub.c -o crt-stub.o
+    i586-kolibrios-ar crs libc.a crt-stub.o
+}
+
+INSTALL()
+{
+    mkdir -p "$SDK_SYSROOT_DIR/lib"
+    cp -f kos-app.lds "$SDK_SYSROOT_DIR/lib/"
+    cp -f libc.a "$SDK_SYSROOT_DIR/lib"
+}
+
+CLEAN()
+{
+    rm -f crt-stub.o libc.a
+}
+
+source ../../scripts/end-recipe