tools: disable LTO for "v8_cppgc_shared" target #38346
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"PushAllRegistersAndIterateStack" is implemented in assembly and called from "stack.cc" via 'extern "C"'. [1] However, LTO does not work well with symbol usage from assembly. [2] This change workarounds the issue by disabling LTO for the target. With GCC 10 and "./configure --enable-lto", compilation succeeds after this change. [1] v8/v8@c10863153 [2] https://gcc.gnu.org/wiki/LinkTimeOptimizationFAQ#Symbol_usage_from_assembly_language Refs: #35957 Refs: #38335 Signed-off-by: Jesse Chan <jc@linux.com>
richardlau
approved these changes
Apr 22, 2021
| @@ -1378,6 +1378,9 @@ | |||
| '<(V8_ROOT)/src/heap/base/worklist.h', | |||
| ], | |||
| 'conditions': [ | |||
| ['enable_lto=="true"', { | |||
| 'cflags_cc': [ '-fno-lto' ], | |||
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This could be set regardless of the enable_lto setting?
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Technically, yes, at least for GCC. But I am not sure about MSVC or Clang. Since enable_lto implies some other conditions, I think it is better to have this conditional.
joyeecheung
reviewed
Apr 22, 2021
joyeecheung
approved these changes
Apr 22, 2021
Trott
approved these changes
Apr 27, 2021
gengjiawen
approved these changes
Apr 29, 2021
|
Landed in 6ca785b |
gengjiawen
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Apr 29, 2021
"PushAllRegistersAndIterateStack" is implemented in assembly and called from "stack.cc" via 'extern "C"'. [1] However, LTO does not work well with symbol usage from assembly. [2] This change workarounds the issue by disabling LTO for the target. With GCC 10 and "./configure --enable-lto", compilation succeeds after this change. [1] v8/v8@c10863153 [2] https://gcc.gnu.org/wiki/LinkTimeOptimizationFAQ#Symbol_usage_from_assembly_language Refs: #35957 Refs: #38335 Signed-off-by: Jesse Chan <jc@linux.com> PR-URL: #38346 Refs: #35957 Refs: #38335 Reviewed-By: Khaidi Chu <i@2333.moe> Reviewed-By: Richard Lau <rlau@redhat.com> Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com> Reviewed-By: Rich Trott <rtrott@gmail.com> Reviewed-By: Jiawen Geng <technicalcute@gmail.com>
targos
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that referenced
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Apr 29, 2021
"PushAllRegistersAndIterateStack" is implemented in assembly and called from "stack.cc" via 'extern "C"'. [1] However, LTO does not work well with symbol usage from assembly. [2] This change workarounds the issue by disabling LTO for the target. With GCC 10 and "./configure --enable-lto", compilation succeeds after this change. [1] v8/v8@c10863153 [2] https://gcc.gnu.org/wiki/LinkTimeOptimizationFAQ#Symbol_usage_from_assembly_language Refs: #35957 Refs: #38335 Signed-off-by: Jesse Chan <jc@linux.com> PR-URL: #38346 Refs: #35957 Refs: #38335 Reviewed-By: Khaidi Chu <i@2333.moe> Reviewed-By: Richard Lau <rlau@redhat.com> Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com> Reviewed-By: Rich Trott <rtrott@gmail.com> Reviewed-By: Jiawen Geng <technicalcute@gmail.com>
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"PushAllRegistersAndIterateStack" is implemented in assembly and
called from "stack.cc" via 'extern "C"'. [1]
However, LTO does not work well with symbol usage from assembly. [2]
This change workarounds the issue by disabling LTO for the target.
With GCC 10 and "./configure --enable-lto", compilation succeeds
after this change.
[1] v8/v8@c10863153
[2] https://gcc.gnu.org/wiki/LinkTimeOptimizationFAQ#Symbol_usage_from_assembly_language
Refs: #35957
Refs: #38335
Signed-off-by: Jesse Chan jc@linux.com