Vendor TCMalloc rather than using OS package with libunwind conflicts (#5113)

This replaces the debian package dependency on tcmalloc with a
submodule. It doesn't seem especially invasive, so I think it might be a
plausible solution to the problems we're having with conflicting
libunwind dependencies in the OS package.

Author: graydon

.gitmodules

@@ -49,3 +49,6 @@
 [submodule "src/rust/soroban/p26"]
 	path = src/rust/soroban/p26
 	url = https://github.com/stellar/rs-soroban-env.git
+[submodule "lib/gperftools"]
+	path = lib/gperftools
+	url = https://github.com/gperftools/gperftools.git

INSTALL.md

@@ -66,7 +66,6 @@ To install Postgresql, follow instructions from the [Postgresql download page](h
 - 64-bit system
 - `clang-format-20` (for `make format` to work)
 - `sed` and `perl`
-- `libgoogle-perftools-dev` (Linux only, for tcmalloc memory allocator)
 - Rust toolchain (see [Installing Rust](#installing-rust) subsection)
   - `cargo` >= 1.74
   - `rust` >= 1.74
@@ -118,7 +117,7 @@ sudo apt install gcc-14 g++-14
 ```zsh
 # common packages
 sudo apt-get update
-sudo apt-get install git build-essential pkg-config autoconf automake libtool bison flex libpq-dev libgoogle-perftools-dev parallel sed perl
+sudo apt-get install git build-essential pkg-config autoconf automake libtool bison flex libpq-dev parallel sed perl
 # if using clang
 sudo apt-get -y install clang-20 llvm-20
 # clang with libc++

common.mk

@@ -2,7 +2,7 @@
 
 AM_CPPFLAGS = -isystem "$(top_srcdir)" -I"$(top_srcdir)/src" -I"$(top_builddir)/src"
 AM_CPPFLAGS += $(libsodium_CFLAGS) $(xdrpp_CFLAGS) $(libmedida_CFLAGS)	\
-	$(soci_CFLAGS) $(sqlite3_CFLAGS) $(libasio_CFLAGS)
+	$(soci_CFLAGS) $(sqlite3_CFLAGS) $(libasio_CFLAGS) $(libtcmalloc_CFLAGS)
 AM_CPPFLAGS += -isystem "$(top_srcdir)/lib"             \
 	-isystem "$(top_srcdir)/lib/autocheck/include"      \
 	-isystem "$(top_srcdir)/lib/cereal/include"         \

configure.ac

@@ -343,19 +343,22 @@ AM_CONDITIONAL(USE_POSTGRES, [test -n "$have_postgres"])
 
 # tcmalloc_minimal - enabled by default on Linux for improved memory allocation performance
 # Disabled when using sanitizers (asan, memcheck, tsan) as they replace malloc
+# Uses vendored gperftools from lib/gperftools
 unset have_tcmalloc
 if test "x$enable_asan" = "xyes" -o "x$enable_memcheck" = "xyes" -o "x$enable_threadsanitizer" = "xyes"; then
     AC_MSG_NOTICE([tcmalloc disabled due to sanitizer being enabled])
 else
     case "${host_os}" in
         linux*)
-            PKG_CHECK_MODULES(libtcmalloc, [libtcmalloc_minimal >= 2.0], [
-                have_tcmalloc=1
-                AC_DEFINE([USE_TCMALLOC], [1], [Define to 1 if using tcmalloc])
-                AC_MSG_NOTICE([tcmalloc_minimal found and will be used])
-            ], [
-                AC_MSG_ERROR([tcmalloc_minimal not found. Install libgoogle-perftools-dev])
-            ])
+            # Configure gperftools for minimal tcmalloc only
+            ac_configure_args="$ac_configure_args --enable-minimal --disable-cpu-profiler --disable-heap-profiler --disable-heap-checker --disable-debugalloc"
+            AC_CONFIG_SUBDIRS([lib/gperftools])
+            have_tcmalloc=1
+            AC_DEFINE([USE_TCMALLOC], [1], [Define to 1 if using tcmalloc])
+            # Use static library with early link order for malloc replacement
+            libtcmalloc_LIBS='$(top_builddir)/lib/gperftools/.libs/libtcmalloc_minimal.a -lpthread'
+            libtcmalloc_CFLAGS='-isystem $(top_srcdir)/lib/gperftools/src'
+            AC_MSG_NOTICE([Using vendored tcmalloc_minimal from lib/gperftools])
             ;;
         *)
             AC_MSG_NOTICE([tcmalloc is only used on Linux, skipping])

docker/Dockerfile.testing

@@ -4,7 +4,7 @@ ENV DEBIAN_FRONTEND=noninteractive
 RUN apt-get update && \
     apt-get -y install iproute2 procps lsb-release \
                        git build-essential pkg-config autoconf automake libtool \
-                       bison flex sed perl libpq-dev parallel libgoogle-perftools-dev \
+                       bison flex sed perl libpq-dev parallel \
                        clang-20 libc++abi-20-dev libc++-20-dev libclang-rt-20-dev \
                        postgresql curl
 

lib/Makefile.am

@@ -1,6 +1,9 @@
 ## Process this file with automake to produce Makefile.in
 
 SUBDIRS = $(PKGCONFIG_SUBDIRS)
+if USE_TCMALLOC
+SUBDIRS += gperftools
+endif
 
 include $(top_srcdir)/common.mk
 

lib/gperftools

@@ -72,10 +72,10 @@ main/XDRFilesSha256.cpp: $(SRC_X_FILES) Makefile $(top_srcdir)/hash-xdrs.sh
 	$(top_srcdir)/hash-xdrs.sh $(top_srcdir)/src/protocol-curr >$@
 endif
 
-stellar_core_LDADD = $(soci_LIBS) $(libmedida_LIBS)		\
+# tcmalloc must be linked early to properly override malloc/free
+stellar_core_LDADD = $(libtcmalloc_LIBS) $(soci_LIBS) $(libmedida_LIBS)		\
 	$(top_builddir)/lib/lib3rdparty.a $(sqlite3_LIBS)	\
-	$(libpq_LIBS) $(xdrpp_LIBS) $(libsodium_LIBS) \
-	$(libtcmalloc_LIBS)
+	$(libpq_LIBS) $(xdrpp_LIBS) $(libsodium_LIBS)
 
 TESTDATA_DIR = testdata
 TEST_FILES = $(TESTDATA_DIR)/stellar-core_example.cfg $(TESTDATA_DIR)/stellar-core_standalone.cfg \