This commit adds a new option to the driver that truncates one file after linking.
Tested likeso: $ gcc hello.c -c $ du -h hello.o 4.0K hello.o $ gcc hello.o -truncate hello $ ./a.out Hello world $ du -h hello.o $ 0 hello.o $ gcc hello.o -truncate gcc: error: missing filename after '-truncate' The motivation for adding this is PR110710. It is used by lto-wrapper to truncate files in a shell-independent manner. Signed-off-by: Peter Damianov <peter0...@disroot.org> --- gcc/common.opt | 5 +++++ gcc/gcc.cc | 13 +++++++++++++ 2 files changed, 18 insertions(+) diff --git a/gcc/common.opt b/gcc/common.opt index ad348844775..3ede2fa8552 100644 --- a/gcc/common.opt +++ b/gcc/common.opt @@ -422,6 +422,11 @@ Display target specific command line options (including assembler and linker opt -time Driver Alias(time) +;; Truncate the file specified after linking. +;; This option is used by lto-wrapper to reduce the peak disk when linking with +;; many .LTRANS units. +Driver Separate Undocumented MissingArgError(missing filename after %qs) + -verbose Driver Alias(v) diff --git a/gcc/gcc.cc b/gcc/gcc.cc index 728332b8153..00017964295 100644 --- a/gcc/gcc.cc +++ b/gcc/gcc.cc @@ -2138,6 +2138,10 @@ static int have_E = 0; /* Pointer to output file name passed in with -o. */ static const char *output_file = 0; +/* Pointer to input file name passed in with -truncate. + This file should be truncated after linking. */ +static const char *totruncate_file = 0; + /* This is the list of suffixes and codes (%g/%u/%U/%j) and the associated temp file. If the HOST_BIT_BUCKET is used for %j, no entry is made for it here. */ @@ -4607,6 +4611,10 @@ driver_handle_option (struct gcc_options *opts, save_switch ("-o", 1, &arg, validated, true); return true; + case OPT_truncate: + totruncate_file = arg; + break; + case OPT_pie: #ifdef ENABLE_DEFAULT_PIE /* -pie is turned on by default. */ @@ -9273,6 +9281,11 @@ driver::maybe_run_linker (const char *argv0) const option). */ error ("%s: linker input file not found: %m", outfiles[i]); } + + if (totruncate_file != NULL && linker_was_run && !seen_error ()) + /* Truncate file specified by -truncate. + Used by lto-wrapper to reduce temporary disk-space usage. */ + truncate(totruncate_file, 0); } /* The end of "main". */ -- 2.39.2