| Message ID | 20200626154927.3185266-1-john@metanate.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | toolchain/toolchain-wrapper: let recent GCC handle SOURCE_DATE_EPOCH | expand |
On Fri, 26 Jun 2020 16:49:27 +0100 John Keeping <john@metanate.com> wrote: > When using precompiled headers, changing any macros defined on the > command line will invalidate the precompiled header. With > toolchain-wrapper adding __DATE__ and __TIME__, any commits to Buildroot > will invalidate incremental builds regardless of whether the precompiled > header actually uses those values (affecting _OVERRIDE_SRCDIR). > > GCC-7 and later support SOURCE_DATE_EPOCH and use it to define __DATE__ > and __TIME__ internally, avoiding any impact on precompiled headers. > > Disable the custom handling in toolchain-wrapper if GCC is version 7 or > newer. > > Signed-off-by: John Keeping <john@metanate.com> > --- > toolchain/toolchain-wrapper.c | 10 ++++++++++ > toolchain/toolchain-wrapper.mk | 3 +++ > 2 files changed, 13 insertions(+) Applied to master, thanks. Thomas
>>>>> "John" == John Keeping <john@metanate.com> writes: > When using precompiled headers, changing any macros defined on the > command line will invalidate the precompiled header. With > toolchain-wrapper adding __DATE__ and __TIME__, any commits to Buildroot > will invalidate incremental builds regardless of whether the precompiled > header actually uses those values (affecting _OVERRIDE_SRCDIR). > GCC-7 and later support SOURCE_DATE_EPOCH and use it to define __DATE__ > and __TIME__ internally, avoiding any impact on precompiled headers. > Disable the custom handling in toolchain-wrapper if GCC is version 7 or > newer. > Signed-off-by: John Keeping <john@metanate.com> Seems pretty safe to add, so: Committed to 2020.02.x and 2020.05.x, thanks.
diff --git a/toolchain/toolchain-wrapper.c b/toolchain/toolchain-wrapper.c index 39e9f0850f..0fb6064b1c 100644 --- a/toolchain/toolchain-wrapper.c +++ b/toolchain/toolchain-wrapper.c @@ -179,6 +179,7 @@ static void check_unsafe_path(const char *arg, } } +#ifdef BR_NEED_SOURCE_DATE_EPOCH /* Returns false if SOURCE_DATE_EPOCH was not defined in the environment. * * Returns true if SOURCE_DATE_EPOCH is in the environment and represent @@ -232,6 +233,15 @@ bool parse_source_date_epoch_from_env(void) } return true; } +#else +bool parse_source_date_epoch_from_env(void) +{ + /* The compiler is recent enough to handle SOURCE_DATE_EPOCH itself + * so we do not need to do anything here. + */ + return false; +} +#endif int main(int argc, char **argv) { diff --git a/toolchain/toolchain-wrapper.mk b/toolchain/toolchain-wrapper.mk index 09dda17890..4d45e3d8a2 100644 --- a/toolchain/toolchain-wrapper.mk +++ b/toolchain/toolchain-wrapper.mk @@ -28,6 +28,9 @@ TOOLCHAIN_WRAPPER_OPTS += -ffile-prefix-map=$(BASE_DIR)=buildroot else TOOLCHAIN_WRAPPER_OPTS += -D__FILE__=\"\" -D__BASE_FILE__=\"\" -Wno-builtin-macro-redefined endif +ifneq ($(BR2_TOOLCHAIN_GCC_AT_LEAST_7),y) +TOOLCHAIN_WRAPPER_OPTS += -DBR_NEED_SOURCE_DATE_EPOCH +endif endif # We create a list like '"-mfoo", "-mbar", "-mbarfoo"' so that each flag is a
When using precompiled headers, changing any macros defined on the command line will invalidate the precompiled header. With toolchain-wrapper adding __DATE__ and __TIME__, any commits to Buildroot will invalidate incremental builds regardless of whether the precompiled header actually uses those values (affecting _OVERRIDE_SRCDIR). GCC-7 and later support SOURCE_DATE_EPOCH and use it to define __DATE__ and __TIME__ internally, avoiding any impact on precompiled headers. Disable the custom handling in toolchain-wrapper if GCC is version 7 or newer. Signed-off-by: John Keeping <john@metanate.com> --- toolchain/toolchain-wrapper.c | 10 ++++++++++ toolchain/toolchain-wrapper.mk | 3 +++ 2 files changed, 13 insertions(+)