| Message ID | 20200512231734.102025-1-maskray@google.com |
|---|---|
| State | New |
| Headers | show |
| Series | Add -fsplit-dwarf | expand |
On Wed, May 13, 2020 at 1:40 AM Fangrui Song via Gcc-patches <gcc-patches@gcc.gnu.org> wrote: > > -fsplit-dwarf is similar to -gsplit-dwarf, but does not enable debugging > information by itself. This makes it easier to be plugged into a build > system without worrying that unnecessary debugging information may be > generated. Hmm. I think having both -fsplit-dwarf and -gsplit-dwarf is confusing. Doesn't feeding -g0 -gsplit-dwarf into the build system work with a later -g then enabling debug info generation? Having said that my preference would be (in the following order): 1) make -gsplit-dwarf not imply -g 2) add -gsplit-dwarf0 implying -g0 (and maybe accept -gsplit-dwarf[012]) for 1) the ship may have sailed. For 2) it might be confused with -gdwarf2 so maybe it should be -g0split-dwarf. Eh. I still like 1) most. Oh, and -gsplit-dwarf is largely unmaintained. Did I mention I dislike -fsplit-dwarf? ;) Richard. > 2020-05-12 Fangrui Song <maskray@google.com> > > PR debug/95096 > * common.opt: Add -fsplit-dwarf. > * doc/invoke.texi: Document it. > --- > gcc/common.opt | 4 ++++ > gcc/doc/invoke.texi | 8 ++++++++ > 2 files changed, 12 insertions(+) > > diff --git a/gcc/common.opt b/gcc/common.opt > index 4464049fc1f..07aa9f28002 100644 > --- a/gcc/common.opt > +++ b/gcc/common.opt > @@ -2515,6 +2515,10 @@ fsingle-precision-constant > Common Report Var(flag_single_precision_constant) Optimization > Convert floating point constants to single precision constants. > > +fsplit-dwarf > +Common Driver Var(dwarf_split_debug_info) Init(0) > +If debug information is enabled, generate debug information in separate .dwo files. > + > fsplit-ivs-in-unroller > Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization > Split lifetimes of induction variables when loops are unrolled. > diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi > index 850aeac033d..6590e60f5b3 100644 > --- a/gcc/doc/invoke.texi > +++ b/gcc/doc/invoke.texi > @@ -448,6 +448,7 @@ Objective-C and Objective-C++ Dialects}. > -femit-struct-debug-detailed@r{[}=@var{spec-list}@r{]} @gol > -fno-eliminate-unused-debug-symbols -femit-class-debug-always @gol > -fno-merge-debug-strings -fno-dwarf2-cfi-asm @gol > +-fsplit-dwarf @gol > -fvar-tracking -fvar-tracking-assignments} > > @item Optimization Options > @@ -8771,6 +8772,13 @@ also be used to change an absolute path to a relative path by using > are location independent, but may require an extra command to tell GDB > where to find the source files. See also @option{-ffile-prefix-map}. > > +@item -fsplit-dwarf > +@opindex fsplit-dwarf > +If DWARF debugging information is enabled, separate as much debugging > +information as possible into a separate output file with the extension > +@file{.dwo}. This is similar to @option{-gsplit-dwarf}, but this option > +does not enable debugging information by itself. > + > @item -fvar-tracking > @opindex fvar-tracking > Run variable tracking pass. It computes where variables are stored at each > -- > 2.26.2.645.ge9eca65c58-goog >
> Did I mention I dislike -fsplit-dwarf? ;)
Seconded, this will be confusing for almost all users. Since the option only
affects debug info generation, it should be prefixed with 'g' in any case.
diff --git a/gcc/common.opt b/gcc/common.opt index 4464049fc1f..07aa9f28002 100644 --- a/gcc/common.opt +++ b/gcc/common.opt @@ -2515,6 +2515,10 @@ fsingle-precision-constant Common Report Var(flag_single_precision_constant) Optimization Convert floating point constants to single precision constants. +fsplit-dwarf +Common Driver Var(dwarf_split_debug_info) Init(0) +If debug information is enabled, generate debug information in separate .dwo files. + fsplit-ivs-in-unroller Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization Split lifetimes of induction variables when loops are unrolled. diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index 850aeac033d..6590e60f5b3 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -448,6 +448,7 @@ Objective-C and Objective-C++ Dialects}. -femit-struct-debug-detailed@r{[}=@var{spec-list}@r{]} @gol -fno-eliminate-unused-debug-symbols -femit-class-debug-always @gol -fno-merge-debug-strings -fno-dwarf2-cfi-asm @gol +-fsplit-dwarf @gol -fvar-tracking -fvar-tracking-assignments} @item Optimization Options @@ -8771,6 +8772,13 @@ also be used to change an absolute path to a relative path by using are location independent, but may require an extra command to tell GDB where to find the source files. See also @option{-ffile-prefix-map}. +@item -fsplit-dwarf +@opindex fsplit-dwarf +If DWARF debugging information is enabled, separate as much debugging +information as possible into a separate output file with the extension +@file{.dwo}. This is similar to @option{-gsplit-dwarf}, but this option +does not enable debugging information by itself. + @item -fvar-tracking @opindex fvar-tracking Run variable tracking pass. It computes where variables are stored at each