gdb.base/break.exp C++ify

Some adjustments to make gdb.base/break.exp work when compiled as a
C++ program.  Passes cleanly with Clang++, but not with G++.  The
latter puts a breakpoint at an unexpected line in one case.  It seems
like a bug that gcc and g++ behave differently here.

gdb/testsuite/ChangeLog:

	* gdb.base/break.exp (func): New.  Use it throughout when
	expecting a function name.

2 files changed, 33 insertions, 22 deletions

diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index e83ec79..c7e2c4c 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,5 +1,10 @@
 2020-09-17  Pedro Alves  <pedro@palves.net>
 
+	* gdb.base/break.exp (func): New.  Use it throughout when
+	expecting a function name.
+
+2020-09-17  Pedro Alves  <pedro@palves.net>
+
 	* gdb.base/display.exp: Issue "set print asm-demangle on".
 
 2020-09-17  Pedro Alves  <pedro@palves.net>
diff --git a/gdb/testsuite/gdb.base/break.exp b/gdb/testsuite/gdb.base/break.exp
index 8c7ce42..35813e3 100644
--- a/gdb/testsuite/gdb.base/break.exp
+++ b/gdb/testsuite/gdb.base/break.exp
@@ -121,16 +121,22 @@ set main_line $bp_location6
 set bp_location7 [gdb_get_line_number "set breakpoint 7 here"]
 set bp_location8 [gdb_get_line_number "set breakpoint 8 here" $srcfile1]
 
+# In C++ mode, we see a full prototype; in C mode, we only see the
+# function name, with no parameter info.
+proc func {name} {
+    return "${name}(?:\(\[^\r\n\]*\))?"
+}
+
 gdb_test "info break" \
     "Num     Type\[ \]+Disp Enb Address\[ \]+What.*
-\[0-9\]+\[\t \]+breakpoint     keep y.* in main at .*$srcfile:$main_line.*
-\[0-9\]+\[\t \]+breakpoint     keep y.* in marker2 at .*$srcfile1:$bp_location8.*
-\[0-9\]+\[\t \]+breakpoint     keep y.* in factorial at .*$srcfile:$bp_location7.*
-\[0-9\]+\[\t \]+breakpoint     keep y.* in main at .*$srcfile:$bp_location1.*
-\[0-9\]+\[\t \]+breakpoint     keep y.* in main at .*$srcfile:$bp_location1.*
-\[0-9\]+\[\t \]+breakpoint     keep y.* in main at .*$srcfile:$bp_location2.*
-\[0-9\]+\[\t \]+breakpoint     keep y.* in multi_line_if_conditional at .*$srcfile:$bp_location3.*
-\[0-9\]+\[\t \]+breakpoint     keep y.* in multi_line_while_conditional at .*$srcfile:$bp_location4" \
+\[0-9\]+\[\t \]+breakpoint     keep y.* in [func main] at .*$srcfile:$main_line.*
+\[0-9\]+\[\t \]+breakpoint     keep y.* in [func marker2] at .*$srcfile1:$bp_location8.*
+\[0-9\]+\[\t \]+breakpoint     keep y.* in [func factorial] at .*$srcfile:$bp_location7.*
+\[0-9\]+\[\t \]+breakpoint     keep y.* in [func main] at .*$srcfile:$bp_location1.*
+\[0-9\]+\[\t \]+breakpoint     keep y.* in [func main] at .*$srcfile:$bp_location1.*
+\[0-9\]+\[\t \]+breakpoint     keep y.* in [func main] at .*$srcfile:$bp_location2.*
+\[0-9\]+\[\t \]+breakpoint     keep y.* in [func multi_line_if_conditional] at .*$srcfile:$bp_location3.*
+\[0-9\]+\[\t \]+breakpoint     keep y.* in [func multi_line_while_conditional] at .*$srcfile:$bp_location4" \
     "breakpoint info"
 
 #
@@ -149,7 +155,7 @@ gdb_test_multiple "info break 2 4 6" "info break 2 4 6" {
 	set see1 1
 	exp_continue
     }
-    -re "2\[\t \]+breakpoint *keep y\[^\r\n\]* in marker2 at \[^\r\n\]*" {
+    -re "2\[\t \]+breakpoint *keep y\[^\r\n\]* in [func marker2] at \[^\r\n\]*" {
 	set see2 1
 	exp_continue
     }
@@ -186,11 +192,11 @@ set see5 0
 set see6 0
 
 gdb_test_multiple "info break 3-5" "info break 3-5" {
-    -re "1\[\t \]+breakpoint *keep y.* in main at .*:$main_line\[^\r\n\]*" {
+    -re "1\[\t \]+breakpoint *keep y.* in [func main] at .*:$main_line\[^\r\n\]*" {
 	set see1 1
 	exp_continue
     }
-    -re "2\[\t \]+breakpoint *keep y\[^\r\n\]* in marker2 at \[^\r\n\]*" {
+    -re "2\[\t \]+breakpoint *keep y\[^\r\n\]* in [func marker2] at \[^\r\n\]*" {
 	set see2 1
 	exp_continue
     }
@@ -243,11 +249,11 @@ set see5 0
 set see6 0
 
 gdb_test_multiple "info break" "check disable with history values" {
-    -re "1\[\t \]+breakpoint *keep y.* in main at .*:$main_line\[^\r\n\]*" {
+    -re "1\[\t \]+breakpoint *keep y.* in [func main] at .*:$main_line\[^\r\n\]*" {
 	set see1 1
 	exp_continue
     }
-    -re "2\[\t \]+breakpoint *keep n\[^\r\n\]* in marker2 at \[^\r\n\]*" {
+    -re "2\[\t \]+breakpoint *keep n\[^\r\n\]* in [func marker2] at \[^\r\n\]*" {
 	set see2 1
 	exp_continue
     }
@@ -289,11 +295,11 @@ set see5 0
 set see6 0
 
 gdb_test_multiple "info break" "check disable with convenience values" {
-    -re "1\[\t \]+breakpoint *keep y.* in main at .*:$main_line\[^\r\n\]*" {
+    -re "1\[\t \]+breakpoint *keep y.* in [func main] at .*:$main_line\[^\r\n\]*" {
 	set see1 1
 	exp_continue
     }
-    -re "2\[\t \]+breakpoint *keep y\[^\r\n\]* in marker2 at \[^\r\n\]*" {
+    -re "2\[\t \]+breakpoint *keep y\[^\r\n\]* in [func marker2] at \[^\r\n\]*" {
 	set see2 1
 	exp_continue
     }
@@ -452,12 +458,12 @@ gdb_test  "tbreak $srcfile:$bp_location11" "Temporary breakpoint.*at.* file .*$s
 # check to see what breakpoints are set (temporary this time)
 #
 gdb_test "info break" "Num     Type.*Disp Enb Address.*What.*\[\r\n\]
-\[0-9\]+\[\t \]+breakpoint     del.*y.*in main at .*$srcfile:$main_line.*\[\r\n\]
-\[0-9\]+\[\t \]+breakpoint     del.*y.*in factorial at .*$srcfile:$bp_location7.*\[\r\n\]
-\[0-9\]+\[\t \]+breakpoint     del.*y.*in main at .*$srcfile:$bp_location1.*\[\r\n\]
-\[0-9\]+\[\t \]+breakpoint     del.*y.*in main at .*$srcfile:$bp_location6.*\[\r\n\]
-\[0-9\]+\[\t \]+breakpoint     del.*y.*in main at .*$srcfile:$bp_location2.*\[\r\n\]
-\[0-9\]+\[\t \]+breakpoint     del.*y.*in main at .*$srcfile:$bp_location11.*" \
+\[0-9\]+\[\t \]+breakpoint     del.*y.*in [func main] at .*$srcfile:$main_line.*\[\r\n\]
+\[0-9\]+\[\t \]+breakpoint     del.*y.*in [func factorial] at .*$srcfile:$bp_location7.*\[\r\n\]
+\[0-9\]+\[\t \]+breakpoint     del.*y.*in [func main] at .*$srcfile:$bp_location1.*\[\r\n\]
+\[0-9\]+\[\t \]+breakpoint     del.*y.*in [func main] at .*$srcfile:$bp_location6.*\[\r\n\]
+\[0-9\]+\[\t \]+breakpoint     del.*y.*in [func main] at .*$srcfile:$bp_location2.*\[\r\n\]
+\[0-9\]+\[\t \]+breakpoint     del.*y.*in [func main] at .*$srcfile:$bp_location11.*" \
     "Temporary breakpoint info"
 
 
@@ -606,7 +612,7 @@ gdb_test "break marker2" \
     "set breakpoint on to-be-called function"
 
 gdb_test "print marker2(99)" \
-    "The program being debugged stopped while in a function called from GDB.\r\nEvaluation of the expression containing the function\r\n.marker2. will be abandoned.\r\nWhen the function is done executing, GDB will silently stop.*" \
+    "The program being debugged stopped while in a function called from GDB.\r\nEvaluation of the expression containing the function\r\n.[func marker2]. will be abandoned.\r\nWhen the function is done executing, GDB will silently stop.*" \
     "hit breakpoint on called function"
 
 # As long as we're stopped (breakpointed) in a called function,