From 8463cc8c2bb879860a04cfe85183eccceae90cfe Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Filip=20Zr=C5=AFst?= <128540+f4z4on@users.noreply.github.com> Date: Wed, 30 Aug 2023 11:48:58 +0200 Subject: [PATCH] Remove CPP when invoking dtrace utility MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We are experiencing an issue when building PHP with DTrace enabled with SystemTap (see GH-11847).† The issue is caused by inappropriate use C preprocessor detected by GNU Autoconf in our “configure” script. C preprocessor configuration found by AC_PROG_CPP macro is portable only to run on files with “.c” extension.‡ However, statically-defined tracing is described by D programs with “.d” extension which causes the issue. We experience this even on typical Linux distribution with GNU Compiler Collection (GCC) unless we override the defaults detected by our “configure” script. Many major Linux distributions use SystemTap to provide “dtrace” utility. It relies on both external C preprocessor and external C compiler. C preprocessor can be customized via CPP environment variable. Similarly, C compiler can be customized via CC environment variable. It also allows customization of C compiler flags via CFLAGS environment variable. We have recently aligned both CPP and CC environment variable with C preprocessor and C compiler we use to build regular C source code as provided by our “configure” script (see GH-11643).* We wanted to allow cross-compilation on Linux for which this was the only blocker. C compiler flags from CFLAGS_CLEAN macro have already been in place since versions 5.4.20 and 5.5.4 from 2013-09-18. We had modified all “dtrace” invocations in the same way to make it look consistent. However, only the C compiler (CC environment variable) is necessary to for cross-compilation. There have never been any reported issue with the C preprocessor. We acknowledge it would be great to allow C preprocessor customization as well. However, the implementation would require a lot of effort to do correctly given the limitations of AC_PROG_CPP macro from GNU Autoconf. This would be further complicated by the fact that all DTrace implementations, not just SystemTap, allow C preprocessor customization but Oracle DTrace, Open DTrace, and their forks do it differently. Nevertheless, they all default to “cpp” utility and they all have or had been working fine. Therefore, we believe simply removing CPP stabilizes “dtrace” invocation on Linux systems with SystemTap and aligns it with other system configurations on other platforms, until someone comes with complete solution with custom “m4” and “make” macros, while our build system on Linux with SystemTap supports cross-compilation. Fixes GH-11847 † https://github.com/php/php-src/issues/11847 ‡ https://www.gnu.org/savannah-checkouts/gnu/autoconf/manual/autoconf-2.71/autoconf.html#index-AC_005fPROG_005fCPP-1 * https://github.com/php/php-src/issues/11643 --- build/php.m4 | 8 ++++---- ext/oci8/config.m4 | 8 ++++---- 2 files changed, 8 insertions(+), 8 deletions(-) diff --git a/build/php.m4 b/build/php.m4 index 921a78eb78e30..80b20410b1818 100644 --- a/build/php.m4 +++ b/build/php.m4 @@ -2389,7 +2389,7 @@ dnl overwritten (Bug 61268). $abs_srcdir/$ac_provsrc:; $ac_bdir[$]ac_hdrobj: $abs_srcdir/$ac_provsrc - CPP="\$(CPP)" CC="\$(CC)" CFLAGS="\$(CFLAGS_CLEAN)" dtrace -h -C -s $ac_srcdir[$]ac_provsrc -o \$[]@.bak && \$(SED) -e 's,PHP_,DTRACE_,g' \$[]@.bak > \$[]@ + CC="\$(CC)" CFLAGS="\$(CFLAGS_CLEAN)" dtrace -h -C -s $ac_srcdir[$]ac_provsrc -o \$[]@.bak && \$(SED) -e 's,PHP_,DTRACE_,g' \$[]@.bak > \$[]@ \$(PHP_DTRACE_OBJS): $ac_bdir[$]ac_hdrobj @@ -2409,12 +2409,12 @@ EOF $ac_bdir[$]ac_provsrc.lo: \$(PHP_DTRACE_OBJS) echo "[#] Generated by Makefile for libtool" > \$[]@ @test -d "$dtrace_lib_dir" || mkdir $dtrace_lib_dir - if CPP="\$(CPP)" CC="\$(CC)" CFLAGS="\$(CFLAGS_CLEAN)" dtrace -G -o $dtrace_d_obj -s $abs_srcdir/$ac_provsrc $dtrace_lib_objs 2> /dev/null && test -f "$dtrace_d_obj"; then [\\] + if CC="\$(CC)" CFLAGS="\$(CFLAGS_CLEAN)" dtrace -G -o $dtrace_d_obj -s $abs_srcdir/$ac_provsrc $dtrace_lib_objs 2> /dev/null && test -f "$dtrace_d_obj"; then [\\] echo "pic_object=['].libs/$dtrace_prov_name[']" >> \$[]@ [;\\] else [\\] echo "pic_object='none'" >> \$[]@ [;\\] fi - if CPP="\$(CPP)" CC="\$(CC)" CFLAGS="\$(CFLAGS_CLEAN)" dtrace -G -o $ac_bdir[$]ac_provsrc.o -s $abs_srcdir/$ac_provsrc $dtrace_nolib_objs 2> /dev/null && test -f "$ac_bdir[$]ac_provsrc.o"; then [\\] + if CC="\$(CC)" CFLAGS="\$(CFLAGS_CLEAN)" dtrace -G -o $ac_bdir[$]ac_provsrc.o -s $abs_srcdir/$ac_provsrc $dtrace_nolib_objs 2> /dev/null && test -f "$ac_bdir[$]ac_provsrc.o"; then [\\] echo "non_pic_object=[']$dtrace_prov_name[']" >> \$[]@ [;\\] else [\\] echo "non_pic_object='none'" >> \$[]@ [;\\] @@ -2426,7 +2426,7 @@ EOF *) cat>>Makefile.objects< \$[]@ + CC="\$(CC)" CFLAGS="\$(CFLAGS_CLEAN)" dtrace -h -C -s $ac_srcdir[$]ac_provsrc -o \$[]@.bak && \$(SED) -e 's,PHPOCI_,DTRACE_,g' \$[]@.bak > \$[]@ \$(OCI8_DTRACE_OBJS): $ac_bdir[$]ac_hdrobj @@ -145,12 +145,12 @@ EOF $ac_bdir[$]ac_provsrc.lo: \$(OCI8_DTRACE_OBJS) echo "[#] Generated by Makefile for libtool" > \$[]@ @test -d "$dtrace_lib_dir" || mkdir $dtrace_lib_dir - if CPP="\$(CPP)" CC="\$(CC)" CFLAGS="\$(CFLAGS_CLEAN)" dtrace -G -o $dtrace_d_obj -s $ac_srcdir[$]ac_provsrc $dtrace_oci8_lib_objs 2> /dev/null && test -f "$dtrace_d_obj"; then [\\] + if CC="\$(CC)" CFLAGS="\$(CFLAGS_CLEAN)" dtrace -G -o $dtrace_d_obj -s $ac_srcdir[$]ac_provsrc $dtrace_oci8_lib_objs 2> /dev/null && test -f "$dtrace_d_obj"; then [\\] echo "pic_object=['].libs/$dtrace_prov_name[']" >> \$[]@ [;\\] else [\\] echo "pic_object='none'" >> \$[]@ [;\\] fi - if CPP="\$(CPP)" CC="\$(CC)" CFLAGS="\$(CFLAGS_CLEAN)" dtrace -G -o $ac_bdir[$]ac_provsrc.o -s $ac_srcdir[$]ac_provsrc $dtrace_nolib_objs 2> /dev/null && test -f "$ac_bdir[$]ac_provsrc.o"; then [\\] + if CC="\$(CC)" CFLAGS="\$(CFLAGS_CLEAN)" dtrace -G -o $ac_bdir[$]ac_provsrc.o -s $ac_srcdir[$]ac_provsrc $dtrace_nolib_objs 2> /dev/null && test -f "$ac_bdir[$]ac_provsrc.o"; then [\\] echo "non_pic_object=[']$dtrace_prov_name[']" >> \$[]@ [;\\] else [\\] echo "non_pic_object='none'" >> \$[]@ [;\\] @@ -162,7 +162,7 @@ EOF AC_MSG_WARN([OCI8 extension: OCI8 DTrace support is not confirmed on this platform]) cat>>Makefile.objects<