build: Add static component pointers for LTO

With GCC's link time optimization, the compiler ends up seeing two
declarations of MCA component structures.  One in the component
itself, which has potentially a component-specific type, and one
in static-components.h, which is just declared as a base MCA
component struct.  The compiler doesn't like this.

This patch adds a level of indirection used by the static component
lookup code.  static-components.h now declares the existance of a
mca_component_t * and the list is of pointers to pointers.  The
MCA base framework has to do an extra dereference, but this is only
in the initialization path.  We also then have to have the actual
pointer exist, so add a macro MCA_BASE_COMPONENT_INIT that we need
to add to every component definition to create the pointer (and
perhaps do more initialization later).

Signed-off-by: Brian Barrett <bbarrett@amazon.com>

Author: bwbarrett

config/opal_mca.m4

@@ -499,7 +499,7 @@ extern "C" {
 
 `cat $outfile.extern`
 
-const mca_base_component_t *mca_$2_base_static_components[[]] = {
+const mca_base_component_t **mca_$2_base_static_components[[]] = {
 `cat $outfile.struct`
   NULL
 };
@@ -763,8 +763,8 @@ AC_DEFUN([MCA_PROCESS_COMPONENT],[
             # $FRAMEWORK_LIB_NAME prefix.
             $7="mca/$2/$3/libmca_$2_$3.la $$7"
         fi
-        echo "extern const mca_base_component_t mca_$2_$3_component;" >> $outfile.extern
-        echo "  &mca_$2_$3_component, " >> $outfile.struct
+        echo "extern const mca_base_component_t *mca_$2_$3_component_ptr;" >> $outfile.extern
+        echo "  &mca_$2_$3_component_ptr," >> $outfile.struct
         $5="$$5 $3"
     fi
 

ompi/mca/bml/r2/bml_r2_component.c

@@ -52,6 +52,7 @@ mca_bml_base_component_2_0_0_t mca_bml_r2_component = {
     },
     .bml_init = mca_bml_r2_component_init,
 };
+MCA_BASE_COMPONENT_INIT(ompi, bml, r2)
 
 static int mca_bml_r2_component_register(void)
 {

ompi/mca/coll/accelerator/coll_accelerator_component.c

@@ -75,6 +75,7 @@ mca_coll_accelerator_component_t mca_coll_accelerator_component = {
     /* Priority: make it above all point to point collectives including self */
     .priority = 78,
 };
+MCA_BASE_COMPONENT_INIT(ompi, coll, accelerator)
 
 
 static int accelerator_register(void)

ompi/mca/coll/acoll/coll_acoll_component.c

@@ -90,6 +90,7 @@ const mca_coll_base_component_3_0_0_t mca_coll_acoll_component = {
     .collm_init_query = mca_coll_acoll_init_query,
     .collm_comm_query = mca_coll_acoll_comm_query,
 };
+MCA_BASE_COMPONENT_INIT(ompi, coll, acoll)
 
 static int acoll_register(void)
 {

ompi/mca/coll/adapt/coll_adapt_component.c

@@ -74,6 +74,7 @@ mca_coll_adapt_component_t mca_coll_adapt_component = {
     /* default values for non-MCA parameters */
     /* Not specifying values here gives us all 0's */
 };
+MCA_BASE_COMPONENT_INIT(ompi, coll, adapt)
 
 /* Open the component */
 static int adapt_open(void)

ompi/mca/coll/basic/coll_basic_component.c

@@ -82,6 +82,7 @@ const mca_coll_base_component_3_0_0_t mca_coll_basic_component = {
     .collm_init_query = mca_coll_basic_init_query,
     .collm_comm_query = mca_coll_basic_comm_query,
 };
+MCA_BASE_COMPONENT_INIT(ompi, coll, basic)
 
 
 static int

ompi/mca/coll/demo/coll_demo_component.c

@@ -82,6 +82,7 @@ const mca_coll_base_component_3_0_0_t mca_coll_demo_component = {
     .collm_init_query = mca_coll_demo_init_query,
     .collm_comm_query = mca_coll_demo_comm_query,
 };
+MCA_BASE_COMPONENT_INIT(ompi, coll, demo)
 
 
 static int demo_register(void)

ompi/mca/coll/ftagree/coll_ftagree_component.c

@@ -78,6 +78,7 @@ const mca_coll_base_component_3_0_0_t mca_coll_ftagree_component = {
     mca_coll_ftagree_init_query,
     mca_coll_ftagree_comm_query
 };
+MCA_BASE_COMPONENT_INIT(ompi, coll, ftagree)
 
 static int
 ftagree_close(void)

ompi/mca/coll/han/coll_han_component.c

@@ -104,6 +104,7 @@ mca_coll_han_component_t mca_coll_han_component = {
     /* workaround for nvcc compiler */
     .dynamic_rules_filename = NULL,
 };
+MCA_BASE_COMPONENT_INIT(ompi, coll, han)
 
 /*
  * Init the component

ompi/mca/coll/hcoll/coll_hcoll_component.c

@@ -64,6 +64,7 @@ mca_coll_hcoll_component_t mca_coll_hcoll_component = {
     0,   /* hcoll_enable */
     NULL /*hcoll version */
 };
+MCA_BASE_COMPONENT_INIT(ompi, coll, hcoll)