starting with version 0.15, userspace-rcu can be compiled with CONFIG_RCU_USE_ATOMIC_BUILTINS. If it is, then any programs using it must be compiled with at least the C11 standard. See: https://github.com/urcu/userspace-rcu/commit/89280d020bf064d1055c360fb9974f128051043f To deal with this, check if compiling with gnu99 fails, and if so, switch to using gnu11. Based-on-patch-by: Yaakov Selkowitz <yselkowi@xxxxxxxxxx> Signed-off-by: Benjamin Marzinski <bmarzins@xxxxxxxxxx> --- Makefile.inc | 2 +- create-config.mk | 13 +++++++++++++ 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/Makefile.inc b/Makefile.inc index 729618bd..65f6efc8 100644 --- a/Makefile.inc +++ b/Makefile.inc @@ -115,7 +115,7 @@ CPPFLAGS := $(FORTIFY_OPT) $(CPPFLAGS) $(D_URCU_VERSION) \ -DRUNTIME_DIR=\"$(runtimedir)\" -DCONFIG_DIR=\"$(TGTDIR)$(configdir)\" \ -DDEFAULT_CONFIGFILE=\"$(TGTDIR)$(configfile)\" -DSTATE_DIR=\"$(TGTDIR)$(statedir)\" \ -DEXTRAVERSION=\"$(EXTRAVERSION)\" -MMD -MP -CFLAGS := -std=gnu99 $(CFLAGS) $(OPTFLAGS) $(WARNFLAGS) -pipe \ +CFLAGS := -std=$(C_STD) $(CFLAGS) $(OPTFLAGS) $(WARNFLAGS) -pipe \ -fexceptions BIN_CFLAGS := -fPIE -DPIE LIB_CFLAGS := -fPIC diff --git a/create-config.mk b/create-config.mk index 8bd2c20c..ab163ed1 100644 --- a/create-config.mk +++ b/create-config.mk @@ -157,6 +157,18 @@ FORTIFY_OPT := $(shell \ echo "-D_FORTIFY_SOURCE=2"; \ fi) +# Check is you can compile with the urcu.h header, using the C99 standard. +# If urcu/config-<arch>.h defines CONFIG_RCU_USE_ATOMIC_BUILTINS, then anything +# including urcu.h must be compiled with at least the C11 standard. See: +# https://github.com/urcu/userspace-rcu/commit/89280d020bf064d1055c360fb9974f128051043f +C_STD := $(shell \ + if printf '$(__HASH__)include <urcu.h>\nint main(void) { return 0; }\n' | $(CC) -o /dev/null -c -xc --std=gnu99 - 2>/dev/null; \ + then \ + echo "gnu99"; \ + else \ + echo "gnu11"; \ + fi) + STACKPROT := all: $(TOPDIR)/config.mk @@ -182,3 +194,4 @@ $(TOPDIR)/config.mk: $(multipathdir)/autoconfig.h @echo "W_MISSING_INITIALIZERS := $(call TEST_MISSING_INITIALIZERS)" >>$@ @echo "W_URCU_TYPE_LIMITS := $(call TEST_URCU_TYPE_LIMITS)" >>$@ @echo "ENABLE_LIBDMMP := $(ENABLE_LIBDMMP)" >>$@ + @echo "C_STD := $(C_STD)" >>$@ -- 2.48.1
