Fix handling of null stap semaphores

[deliverable/binutils-gdb.git] / gdb / testsuite / gdb.base / stap-probe.exp

diff --git a/gdb/testsuite/gdb.base/stap-probe.exp b/gdb/testsuite/gdb.base/stap-probe.exp
index fce528645100c137cee7f1df8d67dc5e0e8e9db0..398bc8936cc8bdabae7763e21100595c266b6770 100644 (file)
--- a/gdb/testsuite/gdb.base/stap-probe.exp
+++ b/gdb/testsuite/gdb.base/stap-probe.exp
@@ -18,14 +18,20 @@ standard_testfile
 # Run the tests.  We run the tests two different ways: once with a
 # plain probe, and once with a probe that has an associated semaphore.
 # This returns -1 on failure to compile or start, 0 otherwise.
-proc stap_test {exec_name {arg ""}} {
+proc stap_test {exec_name {args ""}} {
     global testfile hex srcfile
 
     if {[prepare_for_testing "failed to prepare" ${exec_name} $srcfile \
-          [concat additional_flags=$arg debug]]} {
+          [concat $args debug]]} {
        return -1
     }
 
+    set semaphore_addr_var ""
+    if {[string first "-DUSE_SEMAPHORES" $args] == -1} {
+       gdb_test_no_output "set breakpoint always-inserted on"
+       set semaphore_addr_var [get_hexadecimal_valueof "&relocation_marker" "0"]
+    }
+
     if ![runto_main] {
        return -1
     }
@@ -33,7 +39,7 @@ proc stap_test {exec_name {arg ""}} {
     gdb_test "print \$_probe_argc" "No probe at PC $hex" \
        "check argument not at probe point"
 
-    if {[string first "-DUSE_SEMAPHORES" $arg] != -1} {
+    if {[string first "-DUSE_SEMAPHORES" $args] != -1} {
        gdb_test "info probes stap" \
            "test *user *$hex *$hex .*"
     } else {
@@ -47,6 +53,20 @@ proc stap_test {exec_name {arg ""}} {
        fail "run to -pstap test:user"
     }
 
+    if {[string first "-DUSE_SEMAPHORES" $args] == -1} {
+       set relocation_base \
+          [expr [get_hexadecimal_valueof "&relocation_marker" "0"] - $semaphore_addr_var]
+       if {$relocation_base != 0} {
+          # Checks that GDB doesn't mistakenly relocate and write to null
+          # semaphore addresses.  If it were to relocate a zero-valued
+          # semaphore address and increment the value at that address, we
+          # would expect to see "\200ELF" here instead.
+          gdb_test "p (*(char*) $relocation_base)@4" \
+               " = \"\\\\177ELF\"" \
+               "null semaphore relocation"
+       }
+    }
+
     # Test probe arguments.
     gdb_test "print \$_probe_argc" " = 1" \
     "print \$_probe_argc for probe user"
@@ -97,11 +117,11 @@ proc stap_test {exec_name {arg ""}} {
     return 0
 }
 
-proc stap_test_no_debuginfo {exec_name {arg ""}} {
+proc stap_test_no_debuginfo {exec_name {args ""}} {
     global testfile hex
 
     if {[prepare_for_testing "failed to prepare" ${exec_name} ${testfile}.c \
-          [concat additional_flags=$arg nodebug optimize=-O2]]} {
+          [concat $args nodebug optimize=-O2]]} {
        return -1
     }
 
@@ -168,10 +188,14 @@ with_test_prefix "without semaphore, not optimized" {
        untested "stap probe test failed"
          return -1
     }
+
+    foreach_with_prefix pie { "nopie" "pie" } {
+       stap_test "stap-probe-nosem-noopt-$pie" $pie
+    }
 }
 
 with_test_prefix "with semaphore, not optimized" {
-    stap_test "stap-probe-sem-noopt" "-DUSE_SEMAPHORES"
+    stap_test "stap-probe-sem-noopt" additional_flags=-DUSE_SEMAPHORES
 }
 
 with_test_prefix "without semaphore, optimized" {
@@ -179,5 +203,5 @@ with_test_prefix "without semaphore, optimized" {
 }
 
 with_test_prefix "with semaphore, optimized" {
-    stap_test_no_debuginfo "stap-probe-sem-opt" "-DUSE_SEMAPHORES"
+    stap_test_no_debuginfo "stap-probe-sem-opt" additional_flags=-DUSE_SEMAPHORES
 }