way: first they are compiled to assembly, then some sed'ing is done on
the assembly, and lastly the assembly is compiled to an object file.
This last step is done using ${CC}, and not ${AS}, because when the
compiler is clang, it outputs directives that are too advanced for our
old gas. So we use clang's integrated assembler instead. (When the
compiler is gcc, it just calls gas, and nothing is different, except one
extra fork.)
However, in the .s to .o rules in lib/csu/$ARCH/Makefile, I still passed
CFLAGS to the compiler, instead of ACFLAGS, which are specifically for
compiling .s files.
In case you are using '-g' for debug info anywhere in your CFLAGS, it
causes the .s files to already contain debug information in the assembly
itself. In the next step, the .s files are also compiled using '-g',
and if the compiler is clang, it complains: "error: input can't have
.file dwarf directives when -g is used to generate dwarf debug info for
assembly code".
Fix this by using ${ACFLAGS} for compiling the .s files instead.
Reported by: jasone
MFC after: 1 week
properly reloaded when calling _fini() in large binaries with multiple
TOC sections (e.g. GCC), leading to a segmentation fault. Adding -mlongcall
to crt1 flags causes the compiler to emit explicit TOC load instructions
for all function calls, including _fini().
Reviewed by: kib
Pointy hat to: kib
call preinit, init and fini arrays methods from crt1 for static binaries.
Mark new crt1 with FreeBSD-specific ELF note.
Move some common crt1 code into new MI file ignore_init.c, to reduce
duplication. Also, conservatively adjust nearby sources for style.
Reviewed by: kan
Tested by: andrew (arm), flo (sparc64)
MFC after: 3 weeks
generated from lib/csu/common/crtbrand.c (which ultimately ends up in
executables and shared libraries, via crt1.o, gcrt1.o or Scrt1.o).
For all arches except sparc, gcc emits the section directive for the
abitag struct in crtbrand.c with a PROGBITS type. However, newer
versions of binutils (after 2.16.90) require the section to be of NOTE
type, to guarantee that the .note.ABI-tag section correctly ends up in
the first page of the final executable.
Unfortunately, there is no clean way to tell gcc to use another section
type, so crtbrand.c (or the C files that include it) must be compiled in
multiple steps:
- Compile the .c file to a .s file.
- Edit the .s file to change the 'progbits' type to 'note', for the section
directive that defines the .note.ABI-tag section.
- Compile the .s file to an object file.
These steps are done in the invididual Makefiles for each applicable arch.
Reviewed by: kib
