bpo-38980: Add -fno-semantic-interposition when building with optimizations (GH-22862)
diff --git a/Doc/whatsnew/3.10.rst b/Doc/whatsnew/3.10.rst
index e275a7c..e464be6 100644
--- a/Doc/whatsnew/3.10.rst
+++ b/Doc/whatsnew/3.10.rst
@@ -256,6 +256,14 @@
It is about 36% faster now. (Contributed by Pablo Galindo and Yury Selivanov
in :issue:`42093`.)
+* When building Python with ``--enable-optimizations`` now
+ ``-fno-semantic-interposition`` is added to both the compile and link line.
+ This speeds builds of the Python interpreter created with ``--enable-shared``
+ with ``gcc`` by up to 30%. See `this article
+ <https://developers.redhat.com/blog/2020/06/25/red-hat-enterprise-linux-8-2-brings-faster-python-3-8-run-speeds/>`_
+ for more details. (Contributed by Victor Stinner and Pablo Galindo in
+ :issue:`38980`)
+
Deprecated
==========
diff --git a/Misc/NEWS.d/next/Build/2020-10-21-18-31-54.bpo-38980.xz7BNd.rst b/Misc/NEWS.d/next/Build/2020-10-21-18-31-54.bpo-38980.xz7BNd.rst
new file mode 100644
index 0000000..c9d34cf
--- /dev/null
+++ b/Misc/NEWS.d/next/Build/2020-10-21-18-31-54.bpo-38980.xz7BNd.rst
@@ -0,0 +1,3 @@
+Add ``-fno-semantic-interposition`` to both the compile and link line when
+building with ``--enable-optimizations``. Patch by Victor Stinner and Pablo
+Galindo.
diff --git a/configure b/configure
index 88b7894..df7118f 100755
--- a/configure
+++ b/configure
@@ -6482,6 +6482,14 @@
DEF_MAKE_ALL_RULE="profile-opt"
REQUIRE_PGO="yes"
DEF_MAKE_RULE="build_all"
+ case $CC in
+ *gcc*)
+ CFLAGS_NODIST="$CFLAGS_NODIST -fno-semantic-interposition"
+ LDFLAGS_NODIST="$LDFLAGS_NODIST -fno-semantic-interposition"
+ ;;
+ esac
+
+
else
DEF_MAKE_ALL_RULE="build_all"
REQUIRE_PGO="no"
diff --git a/configure.ac b/configure.ac
index 6ffe90a..c63c1e8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1318,6 +1318,14 @@
DEF_MAKE_ALL_RULE="profile-opt"
REQUIRE_PGO="yes"
DEF_MAKE_RULE="build_all"
+ case $CC in
+ *gcc*)
+ CFLAGS_NODIST="$CFLAGS_NODIST -fno-semantic-interposition"
+ LDFLAGS_NODIST="$LDFLAGS_NODIST -fno-semantic-interposition"
+ ;;
+ esac
+
+
else
DEF_MAKE_ALL_RULE="build_all"
REQUIRE_PGO="no"