https://github.com/python/cpython/commit/8c0a190dd34c220af007896d66850f5676d524d4 commit: 8c0a190dd34c220af007896d66850f5676d524d4 branch: 3.14 author: Miss Islington (bot) <[email protected]> committer: vstinner <[email protected]> date: 2026-03-12T23:13:13Z summary:
[3.14] gh-145801: Use gcc -fprofile-update=atomic for PGO builds (GH-145802) (#145892) gh-145801: Use gcc -fprofile-update=atomic for PGO builds (GH-145802) When Python build is optimized with GCC using PGO, use -fprofile-update=atomic option to use atomic operations when updating profile information. This option reduces the risk of gcov Data Files (.gcda) corruption which can cause random GCC crashes. (cherry picked from commit 08a018ebe0d673e9c352f790d2e4604d69604188) Co-authored-by: Victor Stinner <[email protected]> files: A Misc/NEWS.d/next/Build/2026-03-11-11-58-42.gh-issue-145801.iCXa3v.rst M configure M configure.ac diff --git a/Misc/NEWS.d/next/Build/2026-03-11-11-58-42.gh-issue-145801.iCXa3v.rst b/Misc/NEWS.d/next/Build/2026-03-11-11-58-42.gh-issue-145801.iCXa3v.rst new file mode 100644 index 00000000000000..c5f3982cc5416c --- /dev/null +++ b/Misc/NEWS.d/next/Build/2026-03-11-11-58-42.gh-issue-145801.iCXa3v.rst @@ -0,0 +1,4 @@ +When Python build is optimized with GCC using PGO, use +``-fprofile-update=atomic`` option to use atomic operations when updating +profile information. This option reduces the risk of gcov Data Files (.gcda) +corruption which can cause random GCC crashes. Patch by Victor Stinner. diff --git a/configure b/configure index 60a88b29b538da..3e507be82c046a 100755 --- a/configure +++ b/configure @@ -9049,7 +9049,47 @@ case "$ac_cv_cc_name" in fi ;; gcc) - PGO_PROF_GEN_FLAG="-fprofile-generate" + { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether C compiler accepts -fprofile-update=atomic" >&5 +printf %s "checking whether C compiler accepts -fprofile-update=atomic... " >&6; } +if test ${ax_cv_check_cflags___fprofile_update_atomic+y} +then : + printf %s "(cached) " >&6 +else case e in #( + e) + ax_check_save_flags=$CFLAGS + CFLAGS="$CFLAGS -fprofile-update=atomic" + cat confdefs.h - <<_ACEOF >conftest.$ac_ext +/* end confdefs.h. */ + +int +main (void) +{ + + ; + return 0; +} +_ACEOF +if ac_fn_c_try_compile "$LINENO" +then : + ax_cv_check_cflags___fprofile_update_atomic=yes +else case e in #( + e) ax_cv_check_cflags___fprofile_update_atomic=no ;; +esac +fi +rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext + CFLAGS=$ax_check_save_flags ;; +esac +fi +{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: $ax_cv_check_cflags___fprofile_update_atomic" >&5 +printf "%s\n" "$ax_cv_check_cflags___fprofile_update_atomic" >&6; } +if test "x$ax_cv_check_cflags___fprofile_update_atomic" = xyes +then : + PGO_PROF_GEN_FLAG="-fprofile-generate -fprofile-update=atomic" +else case e in #( + e) PGO_PROF_GEN_FLAG="-fprofile-generate" ;; +esac +fi + PGO_PROF_USE_FLAG="-fprofile-use -fprofile-correction" LLVM_PROF_MERGER="true" LLVM_PROF_FILE="" diff --git a/configure.ac b/configure.ac index ec93a743817268..a1f4a5670957be 100644 --- a/configure.ac +++ b/configure.ac @@ -2072,7 +2072,10 @@ case "$ac_cv_cc_name" in fi ;; gcc) - PGO_PROF_GEN_FLAG="-fprofile-generate" + AX_CHECK_COMPILE_FLAG( + [-fprofile-update=atomic], + [PGO_PROF_GEN_FLAG="-fprofile-generate -fprofile-update=atomic"], + [PGO_PROF_GEN_FLAG="-fprofile-generate"]) PGO_PROF_USE_FLAG="-fprofile-use -fprofile-correction" LLVM_PROF_MERGER="true" LLVM_PROF_FILE="" _______________________________________________ Python-checkins mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3//lists/python-checkins.python.org Member address: [email protected]
