[klibc] mips: use -Ttext-segment when linking shared library

Most architectures use the -Ttext option to move the klibc shared
library out of the way of the normal load address. Unfortunately MIPS
has some extra sections which are positioned before the .text section
and are therefore not repositioned by the -Ttext option.

Fix this by using the -Ttext-segment option. Instead of changing the
address of the .text section, this option changes the .text segment
which happens to include all the special MIPS sections. After this we
can drop the linker script which we no longer need.

Signed-off-by: James Cowgill <james.cowgill@mips.com>
Link: https://www.zytor.com/pipermail/klibc/2018-March/003981.html
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

2 files changed, 6 insertions, 215 deletions

diff --git a/usr/klibc/arch/mips/MCONFIG b/usr/klibc/arch/mips/MCONFIG
index c6331a1dcacc6..7ad6523233628 100644
--- a/usr/klibc/arch/mips/MCONFIG
+++ b/usr/klibc/arch/mips/MCONFIG
@@ -12,4 +12,9 @@ KLIBCOPTFLAGS     += -Os
 KLIBCBITSIZE      = 32
 
 # Extra linkflags when building the shared version of the library
-KLIBCSHAREDFLAGS	= -T $(src)/arch/$(KLIBCARCH)/klibc.ld
+# This address needs to be reachable using normal inter-module
+# calls, and work on the memory models for this architecture
+# 2 MB - normal binaries start at 4 MB
+#
+# Use -Ttext-segment so that the special .MIPS* sections are moved as well.
+KLIBCSHAREDFLAGS     = -Ttext-segment 0x00200000
diff --git a/usr/klibc/arch/mips/klibc.ld b/usr/klibc/arch/mips/klibc.ld
deleted file mode 100644
index 5a2a7a64e7e11..0000000000000
--- a/usr/klibc/arch/mips/klibc.ld
+++ /dev/null
@@ -1,214 +0,0 @@
-/* Linker script for klibc.so, needed because of the the damned
-   GNU ld script headers problem */
-
-ENTRY(__start)
-SECTIONS
-{
-  /* Read-only sections, merged into text segment: */
-  /* This address needs to be reachable using normal inter-module
-      calls, and work on the memory models for this architecture */
-  /* 2 MB -- the normal starting point for text is 4 MB */
-  . = 0x00200400;
-  .interp         : { *(.interp) }
-  .reginfo        : { *(.reginfo) }
-  .dynamic        : { *(.dynamic) }
-  .hash           : { *(.hash) }
-  .dynsym         : { *(.dynsym) }
-  .dynstr         : { *(.dynstr) }
-  .gnu.version    : { *(.gnu.version) }
-  .gnu.version_d  : { *(.gnu.version_d) }
-  .gnu.version_r  : { *(.gnu.version_r) }
-  .rel.dyn        :
-    {
-      *(.rel.init)
-      *(.rel.text .rel.text.* .rel.gnu.linkonce.t.*)
-      *(.rel.fini)
-      *(.rel.rodata .rel.rodata.* .rel.gnu.linkonce.r.*)
-      *(.rel.data .rel.data.* .rel.gnu.linkonce.d.*)
-      *(.rel.tdata .rel.tdata.* .rel.gnu.linkonce.td.*)
-      *(.rel.tbss .rel.tbss.* .rel.gnu.linkonce.tb.*)
-      *(.rel.ctors)
-      *(.rel.dtors)
-      *(.rel.got)
-      *(.rel.sdata .rel.sdata.* .rel.gnu.linkonce.s.*)
-      *(.rel.sbss .rel.sbss.* .rel.gnu.linkonce.sb.*)
-      *(.rel.sdata2 .rel.sdata2.* .rel.gnu.linkonce.s2.*)
-      *(.rel.sbss2 .rel.sbss2.* .rel.gnu.linkonce.sb2.*)
-      *(.rel.bss .rel.bss.* .rel.gnu.linkonce.b.*)
-    }
-  .rela.dyn       :
-    {
-      *(.rela.init)
-      *(.rela.text .rela.text.* .rela.gnu.linkonce.t.*)
-      *(.rela.fini)
-      *(.rela.rodata .rela.rodata.* .rela.gnu.linkonce.r.*)
-      *(.rela.data .rela.data.* .rela.gnu.linkonce.d.*)
-      *(.rela.tdata .rela.tdata.* .rela.gnu.linkonce.td.*)
-      *(.rela.tbss .rela.tbss.* .rela.gnu.linkonce.tb.*)
-      *(.rela.ctors)
-      *(.rela.dtors)
-      *(.rela.got)
-      *(.rela.sdata .rela.sdata.* .rela.gnu.linkonce.s.*)
-      *(.rela.sbss .rela.sbss.* .rela.gnu.linkonce.sb.*)
-      *(.rela.sdata2 .rela.sdata2.* .rela.gnu.linkonce.s2.*)
-      *(.rela.sbss2 .rela.sbss2.* .rela.gnu.linkonce.sb2.*)
-      *(.rela.bss .rela.bss.* .rela.gnu.linkonce.b.*)
-    }
-  .rel.plt        : { *(.rel.plt) }
-  .rela.plt       : { *(.rela.plt) }
-  .init           :
-  {
-    KEEP (*(.init))
-  } =0
-  .plt            : { *(.plt) }
-  .text           :
-  {
-    _ftext = . ;
-    *(.text .stub .text.* .gnu.linkonce.t.*)
-    /* .gnu.warning sections are handled specially by elf32.em.  */
-    *(.gnu.warning)
-    *(.mips16.fn.*) *(.mips16.call.*)
-  } =0
-  .fini           :
-  {
-    KEEP (*(.fini))
-  } =0
-  PROVIDE (__etext = .);
-  PROVIDE (_etext = .);
-  PROVIDE (etext = .);
-  .rodata         : { *(.rodata .rodata.* .gnu.linkonce.r.*) }
-  .rodata1        : { *(.rodata1) }
-  .sdata2         : { *(.sdata2 .sdata2.* .gnu.linkonce.s2.*) }
-  .sbss2          : { *(.sbss2 .sbss2.* .gnu.linkonce.sb2.*) }
-  .eh_frame_hdr : { *(.eh_frame_hdr) }
-  /* Adjust the address for the data segment.  We want to adjust up to
-     the same address within the page on the next page up.  */
-  . = ALIGN(8192);
-  /* Ensure the __preinit_array_start label is properly aligned.  We
-     could instead move the label definition inside the section, but
-     the linker would then create the section even if it turns out to
-     be empty, which isn't pretty.  */
-  . = ALIGN(32 / 8);
-  PROVIDE (__preinit_array_start = .);
-  .preinit_array     : { *(.preinit_array) }
-  PROVIDE (__preinit_array_end = .);
-  PROVIDE (__init_array_start = .);
-  .init_array     : { *(.init_array) }
-  PROVIDE (__init_array_end = .);
-  PROVIDE (__fini_array_start = .);
-  .fini_array     : { *(.fini_array) }
-  PROVIDE (__fini_array_end = .);
-  .data           :
-  {
-    _fdata = . ;
-    *(.data .data.* .gnu.linkonce.d.*)
-    SORT(CONSTRUCTORS)
-  }
-  .data1          : { *(.data1) }
-  .tdata	  : { *(.tdata .tdata.* .gnu.linkonce.td.*) }
-  .tbss		  : { *(.tbss .tbss.* .gnu.linkonce.tb.*) *(.tcommon) }
-  .eh_frame       : { KEEP (*(.eh_frame)) }
-  .gcc_except_table   : { *(.gcc_except_table) }
-  .ctors          :
-  {
-    /* gcc uses crtbegin.o to find the start of
-       the constructors, so we make sure it is
-       first.  Because this is a wildcard, it
-       doesn't matter if the user does not
-       actually link against crtbegin.o; the
-       linker won't look for a file to match a
-       wildcard.  The wildcard also means that it
-       doesn't matter which directory crtbegin.o
-       is in.  */
-    KEEP (*crtbegin*.o(.ctors))
-    /* We don't want to include the .ctor section from
-       from the crtend.o file until after the sorted ctors.
-       The .ctor section from the crtend file contains the
-       end of ctors marker and it must be last */
-    KEEP (*(EXCLUDE_FILE (*crtend*.o ) .ctors))
-    KEEP (*(SORT(.ctors.*)))
-    KEEP (*(.ctors))
-  }
-  .dtors          :
-  {
-    KEEP (*crtbegin*.o(.dtors))
-    KEEP (*(EXCLUDE_FILE (*crtend*.o ) .dtors))
-    KEEP (*(SORT(.dtors.*)))
-    KEEP (*(.dtors))
-  }
-  .jcr            : { KEEP (*(.jcr)) }
-  _gp = ALIGN(16) + 0x7ff0;
-  .got            : { *(.got.plt) *(.got) }
-  /* We want the small data sections together, so single-instruction offsets
-     can access them all, and initialized data all before uninitialized, so
-     we can shorten the on-disk segment size.  */
-  .sdata          :
-  {
-    *(.sdata .sdata.* .gnu.linkonce.s.*)
-  }
-  .lit8           : { *(.lit8) }
-  .lit4           : { *(.lit4) }
-  _edata = .;
-  PROVIDE (edata = .);
-  __bss_start = .;
-  _fbss = .;
-  .sbss           :
-  {
-    PROVIDE (__sbss_start = .);
-    PROVIDE (___sbss_start = .);
-    *(.dynsbss)
-    *(.sbss .sbss.* .gnu.linkonce.sb.*)
-    *(.scommon)
-    PROVIDE (__sbss_end = .);
-    PROVIDE (___sbss_end = .);
-  }
-  .bss            :
-  {
-   *(.dynbss)
-   *(.bss .bss.* .gnu.linkonce.b.*)
-   *(COMMON)
-   /* Align here to ensure that the .bss section occupies space up to
-      _end.  Align after .bss to ensure correct alignment even if the
-      .bss section disappears because there are no input sections.  */
-   . = ALIGN(32 / 8);
-  }
-  . = ALIGN(32 / 8);
-  _end = .;
-  PROVIDE (end = .);
-  /* Stabs debugging sections.  */
-  .stab          0 : { *(.stab) }
-  .stabstr       0 : { *(.stabstr) }
-  .stab.excl     0 : { *(.stab.excl) }
-  .stab.exclstr  0 : { *(.stab.exclstr) }
-  .stab.index    0 : { *(.stab.index) }
-  .stab.indexstr 0 : { *(.stab.indexstr) }
-  .comment       0 : { *(.comment) }
-  /* DWARF debug sections.
-     Symbols in the DWARF debugging sections are relative to the beginning
-     of the section so we begin them at 0.  */
-  /* DWARF 1 */
-  .debug          0 : { *(.debug) }
-  .line           0 : { *(.line) }
-  /* GNU DWARF 1 extensions */
-  .debug_srcinfo  0 : { *(.debug_srcinfo) }
-  .debug_sfnames  0 : { *(.debug_sfnames) }
-  /* DWARF 1.1 and DWARF 2 */
-  .debug_aranges  0 : { *(.debug_aranges) }
-  .debug_pubnames 0 : { *(.debug_pubnames) }
-  /* DWARF 2 */
-  .debug_info     0 : { *(.debug_info .gnu.linkonce.wi.*) }
-  .debug_abbrev   0 : { *(.debug_abbrev) }
-  .debug_line     0 : { *(.debug_line) }
-  .debug_frame    0 : { *(.debug_frame) }
-  .debug_str      0 : { *(.debug_str) }
-  .debug_loc      0 : { *(.debug_loc) }
-  .debug_macinfo  0 : { *(.debug_macinfo) }
-  /* SGI/MIPS DWARF 2 extensions */
-  .debug_weaknames 0 : { *(.debug_weaknames) }
-  .debug_funcnames 0 : { *(.debug_funcnames) }
-  .debug_typenames 0 : { *(.debug_typenames) }
-  .debug_varnames  0 : { *(.debug_varnames) }
-  .gptab.sdata : { *(.gptab.data) *(.gptab.sdata) }
-  .gptab.sbss : { *(.gptab.bss) *(.gptab.sbss) }
-  /DISCARD/ : { *(.note.GNU-stack) }
-}