From: Ben Pfaff Date: Wed, 6 Apr 2005 18:47:14 +0000 (+0000) Subject: Always use a custom linker script, to avoid oddities in the default. X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=383b2e8052badc1865f19e881afb8b5cdb63ff2e;p=pintos-anon Always use a custom linker script, to avoid oddities in the default. Put linker scripts in lib/user. Eliminate redundant dependency in Makefile.userprog. Document change. --- diff --git a/doc/vm.texi b/doc/vm.texi index 42bb3ce..99f4f4f 100644 --- a/doc/vm.texi +++ b/doc/vm.texi @@ -460,7 +460,7 @@ such as Linux do not load partial pages lazily. Incidentally, if you have trouble handling the third case above, you can eliminate it temporarily by linking the test programs with a -special ``linker script.'' Read @file{tests/userprog/Makefile} for +special ``linker script.'' Read @file{Makefile.userprog} for details. We will not test your submission with this special linker script, so the code you turn in must properly handle all cases. diff --git a/src/Makefile.userprog b/src/Makefile.userprog index c5e6f3d..2ecb8e7 100644 --- a/src/Makefile.userprog +++ b/src/Makefile.userprog @@ -10,8 +10,12 @@ DEFINES = -DPINTOS -DUSER CPPFLAGS = -nostdinc -I$(SRCDIR) -I- -I$(SRCDIR)/lib -I$(SRCDIR)/lib/user -I. # Linker flags. -LDFLAGS = -nostdlib -static +LDFLAGS = -nostdlib -static -Wl,-T,$(LDSCRIPT) LDLIBS = $(shell $(CC) -print-libgcc-file-name) +LDSCRIPT = $(SRCDIR)/lib/user/normal.lds +# Uncomment the following line to round up section sizes +# to full pages (for debugging only). +#LDSCRIPT = $(SRCDIR)/lib/user/fullpage.lds # C library sources linked into every test program. LIB_SRC = lib/debug.c # Debug code. @@ -34,14 +38,12 @@ all: $(PROGS) define TEMPLATE $(2)_OBJ = $(patsubst %.c,%.o,$(patsubst %.S,%.o,$($(2)_SRC))) -$(1): $$($(2)_OBJ) $$(LIB) - $$(CC) $$(LDFLAGS) $$^ $$(LDLIBS) -o $$@ +$(1): $$($(2)_OBJ) $$(LIB) $$(LDSCRIPT) + $$(CC) $$(LDFLAGS) $$($(2)_OBJ) $$(LIB) $$(LDLIBS) -o $$@ endef $(foreach prog,$(PROGS),$(eval $(call TEMPLATE,$(prog),$(subst -,_,$(prog))))) -$(PROGS): $(LIB) - libc.a: $(LIB_OBJ) rm -f $@ ar r $@ $^ diff --git a/src/lib/user/fullpage.lds b/src/lib/user/fullpage.lds new file mode 100644 index 0000000..b438695 --- /dev/null +++ b/src/lib/user/fullpage.lds @@ -0,0 +1,50 @@ +OUTPUT_FORMAT("elf32-i386") +OUTPUT_ARCH(i386) +ENTRY(_start) + +SECTIONS +{ + /* Read-only sections, merged into text segment: */ + . = 0x08048000 + SIZEOF_HEADERS; + .text : { *(.text) . = ALIGN(0x1000); } = 0x90 + .rodata : { *(.rodata) . = ALIGN(0x1000); } + .data : { *(.data) . = ALIGN(0x1000); } + .bss : { *(.bss) . = ALIGN(0x1000); } + + /* 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) } + /DISCARD/ : { *(.note.GNU-stack) } + /DISCARD/ : { *(.eh_frame) } +} diff --git a/src/lib/user/normal.lds b/src/lib/user/normal.lds new file mode 100644 index 0000000..e4ca5db --- /dev/null +++ b/src/lib/user/normal.lds @@ -0,0 +1,56 @@ +OUTPUT_FORMAT("elf32-i386") +OUTPUT_ARCH(i386) +ENTRY(_start) + +SECTIONS +{ + /* Read-only sections, merged into text segment: */ + . = 0x08048000 + SIZEOF_HEADERS; + .text : { *(.text) } = 0x90 + .rodata : { *(.rodata) } + + /* 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 (0x1000) - ((0x1000 - .) & (0x1000 - 1)); + . = DATA_SEGMENT_ALIGN (0x1000, 0x1000); + + .data : { *(.data) } + .bss : { *(.bss) } + + /* 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) } + /DISCARD/ : { *(.note.GNU-stack) } + /DISCARD/ : { *(.eh_frame) } +} diff --git a/src/tests/userprog/Makefile b/src/tests/userprog/Makefile index 291cf75..2aad5a3 100644 --- a/src/tests/userprog/Makefile +++ b/src/tests/userprog/Makefile @@ -14,7 +14,3 @@ recursor_SRC = recursor.c shell_SRC = shell.c include $(SRCDIR)/Makefile.userprog - -# Uncomment the line below to round up segment sizes to full pages for -# testing purposes only. -#LDFLAGS += -Wl,-T,fullpage.x diff --git a/src/tests/userprog/fullpage.x b/src/tests/userprog/fullpage.x deleted file mode 100644 index 2fb94e1..0000000 --- a/src/tests/userprog/fullpage.x +++ /dev/null @@ -1,24 +0,0 @@ -/* Default linker script, for normal executables */ -OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386") -OUTPUT_ARCH(i386) -ENTRY(_start) -SECTIONS -{ - . = 0x08048000 + SIZEOF_HEADERS; - .text : { - *(.text .text.*) - . = ALIGN(0x1000); - } =0x90909090 - .rodata : { - *(.rodata .rodata.*) - . = ALIGN(0x1000); - } - .data : { - *(.data .data.*) - . = ALIGN(0x1000); - } - .bss : { - *(.bss .bss.*) - . = ALIGN(0x1000); - } -}