gdb/testsuite: remove definition of true/false from gdb_compiler_info

Since pretty much forever the get_compiler_info function has included
these lines:

    # Most compilers will evaluate comparisons and other boolean
    # operations to 0 or 1.
    uplevel \#0 { set true 1 }
    uplevel \#0 { set false 0 }

These define global variables true (to 1) and false (to 0).

It seems odd to me that these globals are defined in
get_compiler_info, I guess maybe the original thinking was that if a
compiler had different true/false values then we would detect it there
and define true/false differently.

I don't think we should be bundling this logic into get_compiler_info,
it seems weird to me that in order to use $true/$false a user needs to
first call get_compiler_info.

It would be better I think if each test script that wants these
variables just defined them itself, if in the future we did need
different true/false values based on compiler version then we'd just
do:

  if { [test_compiler_info "some_pattern"] } {
    # Defined true/false one way...
  } else {
    # Defined true/false another way...
  }

But given the current true/false definitions have been in place since
at least 1999, I suspect this will not be needed any time soon.

Given that the definitions of true/false are so simple, right now my
suggestion is just to define them in each test script that wants
them (there's not that many).  If we ever did need more complex logic
then we can always add a function in gdb.exp that sets up these
globals, but that seems overkill for now.

There should be no change in what is tested after this commit.

7 files changed, 22 insertions, 5 deletions

diff --git a/gdb/testsuite/gdb.base/all-bin.exp b/gdb/testsuite/gdb.base/all-bin.exp
index 5d493e6..1f48121 100644
--- a/gdb/testsuite/gdb.base/all-bin.exp
+++ b/gdb/testsuite/gdb.base/all-bin.exp
@@ -46,6 +46,10 @@ if ![runto_main] then {
     return
 }
 
+# These are used as expected result values.
+set false 0
+set true 1
+
 gdb_test "next" "return 0;" "continuing after dummy()"
 
 gdb_test "print v_int+v_char" " = 71" "print value of v_int+v_char"
diff --git a/gdb/testsuite/gdb.base/eval-skip.exp b/gdb/testsuite/gdb.base/eval-skip.exp
index 218aaab..81b37d1 100644
--- a/gdb/testsuite/gdb.base/eval-skip.exp
+++ b/gdb/testsuite/gdb.base/eval-skip.exp
@@ -51,6 +51,9 @@ if ![runto_main] then {
     return
 }
 
+# This is used as an expected result value.
+set false 0
+
 gdb_test_no_output "set variable x=14" "set variable x=14"
 gdb_test_no_output "set variable y=2" "set variable y=2"
 gdb_test_no_output "set variable z=2" "set variable z=2"
diff --git a/gdb/testsuite/gdb.base/exprs.exp b/gdb/testsuite/gdb.base/exprs.exp
index 83bc60a..dfe0ec9 100644
--- a/gdb/testsuite/gdb.base/exprs.exp
+++ b/gdb/testsuite/gdb.base/exprs.exp
@@ -41,6 +41,10 @@ if ![runto_main] then {
     return
 }
 
+# These are used as expected result values.
+set false 0
+set true 1
+
 proc test_expr { args } {
     if { [llength $args] % 2 } {
 	warning "an even # of arguments should be passed to test_expr"
diff --git a/gdb/testsuite/gdb.base/miscexprs.exp b/gdb/testsuite/gdb.base/miscexprs.exp
index cac8cf2..f633d14 100644
--- a/gdb/testsuite/gdb.base/miscexprs.exp
+++ b/gdb/testsuite/gdb.base/miscexprs.exp
@@ -59,6 +59,9 @@ if ![runto_main] then {
     return
 }
 
+# This is used as an expected result value.
+set false 0
+
 gdb_test "break marker1" ".*" ""
 
 gdb_test "cont" \
diff --git a/gdb/testsuite/gdb.base/pointers.exp b/gdb/testsuite/gdb.base/pointers.exp
index e640661..586f85a 100644
--- a/gdb/testsuite/gdb.base/pointers.exp
+++ b/gdb/testsuite/gdb.base/pointers.exp
@@ -48,6 +48,10 @@ if ![runto_main] then {
     return
 }
 
+# These are used as expected result values.
+set false 0
+set true 1
+
 gdb_test "next " "more_code.*;" "continuing after dummy()"
 
 
diff --git a/gdb/testsuite/gdb.base/relational.exp b/gdb/testsuite/gdb.base/relational.exp
index 8583983..87ccb9f 100644
--- a/gdb/testsuite/gdb.base/relational.exp
+++ b/gdb/testsuite/gdb.base/relational.exp
@@ -42,6 +42,10 @@ if ![runto_main] then {
     return
 }
 
+# These are used as expected result values.
+set false 0
+set true 1
+
 #
 # test expressions with "int" types
 #
diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
index 37accd9..75efc4a 100644
--- a/gdb/testsuite/lib/gdb.exp
+++ b/gdb/testsuite/lib/gdb.exp
@@ -4191,11 +4191,6 @@ proc get_compiler_info {{language "c"}} {
     # Log what happened.
     verbose -log "get_compiler_info: $compiler_info"
 
-    # Most compilers will evaluate comparisons and other boolean
-    # operations to 0 or 1.
-    uplevel \#0 { set true 1 }
-    uplevel \#0 { set false 0 }
-
     return 0
 }