-*- text -*-
-* The linker script has a new command to insert a timestamp
- TIMESTAMP
- inserts the current time (seconds since Epoch) as a 64-bit value
-
-* The linker script syntax has new commands for debugging a linker script
- DEBUG ON turns on debugging
- DEBUG OFF turns off debugging
-
-* The linker script syntax has new commands for handling CRC-32/64 calculations
- on the '.text' section
- It uses code from https://www.libcrc.org/
-
- DIGEST "<label>[#<endian>]" "CRC32" (start, end)
- DIGEST "<label>[#<endian>]" "CRC64-ECMA" (start, end)
- DIGEST "<label>[#<endian>]" "CRC64-GO-ISO" (start, end)
- DIGEST "<label>[#<endian>]" "CRC64-GO-ISO-R" (start, end)
- DIGEST "<label>[#<endian>]" "CRC64-WE" (start, end)
- DIGEST "<label>[#<endian>]" "CRC64-XZ" (start, end)
- DIGEST "<label>[#<endian>]" POLY (<params>) (start, end)
- DIGEST TABLE "<label>[#<endian>]"
-
- The CRC32, CRC64-ECMA, CRC64-ISO, CRC64-WE and POLY defines
- the polynome to use and reserves space for the 32/64-bit CRC in the
- current section (default ".text"). It also defines a label "<label>".
- The endian can be specified through "#BE" or "#LE" modifiers for
- big endian or little endian. This overrides the "-BE" or "-LE" switches on the
- command line. If no specification is used, little endian
- digest and table will be emitted.
- The generated label does not include the modifier.
-
- When generating a custom polynome you have to supply parameters
- in the following order
- * size {32 | 64 }
- * polynome
- * initial initial value of crc
- * xor value xor with this before returning result
- * input reflect bitreverse input data
- * output reflect bitreverse result
- * reciprocal bitreverse polynome
-
- These terms are explained at
- http://www.sunshine2k.de/articles/coding/crc/understanding_crc.html
-
- The 32 bit DIGEST <polynome> command defines some global symbols.
- ___CRC32___ is the address of the CRC64 checksum
- ___CRC32_START___ is the address where CRC calculation starts
- ___CRC32_END___ The CRC calculation ends before this address.
-
- The 64-bit DIGEST <polynome> command defines some global symbols.
- ___CRC64___ is the address of the CRC64 checksum
- ___CRC64_START___ is the address where CRC calculation starts
- ___CRC64_END___ The CRC calculation ends before this address.
-
- All three symbols must refer to addresses in the selected section.
- If they are defined at the end of the linking process, then
- the CRC## will be calculated between
-
- ___CRC##_START___ .. ___CRC##_END___ -1
-
- and the result will be inserted at ___CRC##___.
-
- ___CRC##___ must be outside the region where CRC is calculated
-
- The DIGEST TABLE command generates a table for CRC generation.
- A table is not neccessary, but will speed up the calculation.
- It defines the ___CRC##_TABLE___ symbol at the start of the table.
- The user may choose to add this table to his code instead of using
- the linker.
-
-* The linker script syntax has two new commands for inserting text into output
- sections:
- ASCII (<size>) "string"
- This will reserve a zero filled block of <size> bytes at the current
- location and insert "string" at the beginning of the block. If the string
- is too long, it will be truncated.
- ASCIZ "string"
+* The linker script syntax has a new command for output sections: ASCIZ "string"
This will insert a zero-terminated string at the current location.
Changes in 2.40:
re-enabled via the --warn-rwx-segments option.
New configure options can also control these new features:
-
+
--enable-warn-execstack=no
will disable the warnings about creating an executable stack.
-
+
--enable-warn-execstack=yes
will make --warn-execstack enabled by default.
-
+
--enable-warn-rwx-segments=no
will make --no-warn-rwx-segments enabled by default.
-
+
--enable-default-execstack=no
will stop the creation of an executable stack simply because an input file
is missing a .note.GNU-stack section, even on architectures where this
projects / thirdparty / binutils-gdb.git / blobdiff