| From: Richard Purdie <richard.purdie@linuxfoundation.org> |
| Subject: [PATCH 3/5] gcc: Add --nostdlib++ option |
| |
| [gcc-runtime builds libstdc++ separately from gcc-cross-*. Its configure tests using g++ |
| will not run correctly since by default the linker will try to link against libstdc++ |
| which shouldn't exist yet. We need an option to disable -lstdc++ |
| option whilst leaving -lc, -lgcc and other automatic library dependencies added by gcc |
| driver. This patch adds such an option which only disables the -lstdc++.] |
| |
| [A "standard" gcc build uses xgcc and hence avoids this. We should ask upstream how to |
| do this officially, the likely answer is don't build libstdc++ separately.] |
| |
| OpenEmbedded/Yocto Project builds libgcc and the other gcc runtime libraries |
| separately from the compiler and slightly differently to the standard gcc build. |
| |
| In general this works well but in trying to build them separately we run into |
| an issue since we're using our gcc, not xgcc and there is no way to tell configure |
| to use libgcc but not look for libstdc++. |
| |
| This adds such an option allowing such configurations to work. |
| |
| 2021-10-26 Richard Purdie <richard.purdie@linuxfoundation.org> |
| |
| gcc/c-family/ChangeLog: |
| |
| * c.opt: Add --nostdlib++ option |
| |
| gcc/cp/ChangeLog: |
| |
| * g++spec.c (lang_specific_driver): Add --nostdlib++ option |
| |
| gcc/ChangeLog: |
| |
| * doc/invoke.texi: Document --nostdlib++ option |
| * gcc.c: Add --nostdlib++ option |
| |
| Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org> |
| |
| Upstream-Status: Submitted [https://gcc.gnu.org/pipermail/gcc-patches/2021-October/582724.html] |
| --- |
| gcc/c-family/c.opt | 4 ++++ |
| gcc/cp/g++spec.c | 1 + |
| gcc/doc/invoke.texi | 8 +++++++- |
| gcc/gcc.c | 1 + |
| 4 files changed, 13 insertions(+), 1 deletion(-) |
| |
| Index: gcc-11.2.0/gcc/c-family/c.opt |
| =================================================================== |
| --- gcc-11.2.0.orig/gcc/c-family/c.opt |
| +++ gcc-11.2.0/gcc/c-family/c.opt |
| @@ -2153,6 +2153,10 @@ nostdinc++ |
| C++ ObjC++ |
| Do not search standard system include directories for C++. |
| |
| +nostdlib++ |
| +Driver |
| +Do not link standard C++ runtime library |
| + |
| o |
| C ObjC C++ ObjC++ Joined Separate |
| ; Documented in common.opt |
| Index: gcc-11.2.0/gcc/cp/g++spec.c |
| =================================================================== |
| --- gcc-11.2.0.orig/gcc/cp/g++spec.c |
| +++ gcc-11.2.0/gcc/cp/g++spec.c |
| @@ -159,6 +159,7 @@ lang_specific_driver (struct cl_decoded_ |
| switch (decoded_options[i].opt_index) |
| { |
| case OPT_nostdlib: |
| + case OPT_nostdlib__: |
| case OPT_nodefaultlibs: |
| library = -1; |
| break; |
| Index: gcc-11.2.0/gcc/doc/invoke.texi |
| =================================================================== |
| --- gcc-11.2.0.orig/gcc/doc/invoke.texi |
| +++ gcc-11.2.0/gcc/doc/invoke.texi |
| @@ -239,6 +239,7 @@ in the following sections. |
| -fno-weak -nostdinc++ @gol |
| -fvisibility-inlines-hidden @gol |
| -fvisibility-ms-compat @gol |
| +-nostdlib++ @gol |
| -fext-numeric-literals @gol |
| -flang-info-include-translate@r{[}=@var{header}@r{]} @gol |
| -flang-info-include-translate-not @gol |
| @@ -632,7 +633,7 @@ Objective-C and Objective-C++ Dialects}. |
| -pie -pthread -r -rdynamic @gol |
| -s -static -static-pie -static-libgcc -static-libstdc++ @gol |
| -static-libasan -static-libtsan -static-liblsan -static-libubsan @gol |
| --shared -shared-libgcc -symbolic @gol |
| +-shared -shared-libgcc -symbolic -nostdlib++ @gol |
| -T @var{script} -Wl,@var{option} -Xlinker @var{option} @gol |
| -u @var{symbol} -z @var{keyword}} |
| |
| @@ -15721,6 +15722,11 @@ Specify that the program entry point is |
| interpreted by the linker; the GNU linker accepts either a symbol name |
| or an address. |
| |
| +@item -nostdlib++ |
| +@opindex nostdlib++ |
| +Do not use the standard system C++ runtime libraries when linking. |
| +Only the libraries you specify will be passed to the linker. |
| + |
| @item -pie |
| @opindex pie |
| Produce a dynamically linked position independent executable on targets |
| Index: gcc-11.2.0/gcc/gcc.c |
| =================================================================== |
| --- gcc-11.2.0.orig/gcc/gcc.c |
| +++ gcc-11.2.0/gcc/gcc.c |
| @@ -1162,6 +1162,7 @@ proper position among the other output f |
| %(mflib) " STACK_SPLIT_SPEC "\ |
| %{fprofile-arcs|fprofile-generate*|coverage:-lgcov} " SANITIZER_SPEC " \ |
| %{!nostdlib:%{!r:%{!nodefaultlibs:%(link_ssp) %(link_gcc_c_sequence)}}}\ |
| + %{!nostdlib++:}\ |
| %{!nostdlib:%{!r:%{!nostartfiles:%E}}} %{T*} \n%(post_link) }}}}}}" |
| #endif |
| |