libgccjit: Add a function to check if LTO is supported

Author: antoyo

gcc/jit/Make-lang.in

@@ -130,6 +130,10 @@ jit.serial = $(LIBGCCJIT_FILENAME)
 # Tell GNU make to ignore these if they exist.
 .PHONY: jit
 
+CFLAGS-jit/libgccjit.o += -DDEFAULT_TARGET_VERSION=\"$(version)\" \
+	-DDEFAULT_TARGET_MACHINE=\"$(target_noncanonical)\" \
+	-DSTANDARD_LIBEXEC_PREFIX=\"$(libexecdir)/gcc/\"
+
 JIT_OBJS = attribs.o \
 	jit/dummy-frontend.o \
 	jit/libgccjit.o \

gcc/jit/libgccjit.cc

@@ -4920,3 +4920,18 @@ gcc_jit_function_set_location (gcc_jit_function *func,
 
   func->set_loc (loc);
 }
+
+bool
+gcc_jit_is_lto_supported ()
+{
+#ifdef ENABLE_LTO
+  char lto1_path[PATH_MAX];
+  snprintf (lto1_path, sizeof(lto1_path), "%s%s/%s/lto1",
+    STANDARD_LIBEXEC_PREFIX, DEFAULT_TARGET_MACHINE, DEFAULT_TARGET_VERSION);
+  if (access (lto1_path, X_OK) == 0) {
+    return true;
+  }
+#endif
+
+  return false;
+}

gcc/jit/libgccjit.h

@@ -2332,6 +2332,9 @@ extern void
 gcc_jit_rvalue_set_location (gcc_jit_rvalue *rvalue,
 			     gcc_jit_location *loc);
 
+extern bool
+gcc_jit_is_lto_supported ();
+
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */

gcc/jit/libgccjit.map

@@ -388,3 +388,8 @@ LIBGCCJIT_ABI_45{
   global:
     gcc_jit_lvalue_set_name;
 } LIBGCCJIT_ABI_44;
+
+LIBGCCJIT_ABI_46 {
+  global:
+    gcc_jit_is_lto_supported;
+} LIBGCCJIT_ABI_45;