Hi Guys,
I would like to make a change to the way %* behaves in spec strings.
Currently whenever %* is encountered the text that was previously
matched is substituted, followed by a space. Thus %{foo=*:bar%*baz}
would match -foo=4 and insert 'bar4 baz'. I would like to change this
so that the space is only inserted if %* is at the end of a spec
sequence. (In all of the strings currently built in to gcc this is
the case, so my patch will not change current behaviour).
The motivation is that I want to construct a pathname based on a
command line option using a spec string like this:
%{mmcu=*:--script=%*/memory.ld}
So that if the user invokes -mmcu=msp430f2617 then gcc will generate:
--script=msp430f2617/memory.ld
A spec string like this however:
%{mmcu=*:--script=%*}/memory.ld
would match the current behaviour and generate:
--script=msp430f2617 /memory.ld
As a secondary feature of the patch I have also updated the
documentation to explicitly state when a space will be inserted into
the generated text.
I have tested the patch and found no regressions using an
i686-pc-liunx-gnu toolchain and an msp430-elf toolchain.
OK to apply ?
Cheers
Nick
gcc/ChangeLog
2013-10-17 Nick Clifton <ni...@redhat.com>
* gcc.c (do_spec_1): Do not insert a space after a %* substitution
unless it is the last part of a spec substring.
* doc/invoke.texi (Spec Files): Document space insertion
behaviour of %*.
Index: gcc/doc/invoke.texi
===================================================================
--- gcc/doc/invoke.texi (revision 203750)
+++ gcc/doc/invoke.texi (working copy)
@@ -10929,6 +10929,22 @@
for each matching switch, with the @code{%*} replaced by the part of
that switch matching the @code{*}.
+If @code{%*} appears as the last part of a spec sequence then a space
+will added after the end of the last substitution. If there is more
+text in the sequence however then a space will not be generated. This
+allows the @code{%*} substitution to be used as part of a larger
+string. For example, a spec string like this:
+
+@smallexample
+%@{mcu=*:--script=%*/memory.ld@}
+@end smallexample
+
+when matching an option like @code{-mcu=newchip} will produce:
+
+@smallexample
+--script=newchip/memory.ld
+@end smallexample
+
@item %@{.@code{S}:@code{X}@}
Substitutes @code{X}, if processing a file with suffix @code{S}.
Index: gcc/gcc.c
===================================================================
--- gcc/gcc.c (revision 203750)
+++ gcc/gcc.c (working copy)
@@ -388,7 +388,8 @@
%2 process CC1PLUS_SPEC as a spec.
%* substitute the variable part of a matched option. (See below.)
Note that each comma in the substituted string is replaced by
- a single space.
+ a single space. A space is appended after the last substitution
+ unless there is more text in current sequence.
%<S remove all occurrences of -S from the command line.
Note - this command is position dependent. % commands in the
spec string before this one will see -S, % commands in the
@@ -422,7 +423,9 @@
once, no matter how many such switches appeared. However,
if %* appears somewhere in X, then X will be substituted
once for each matching switch, with the %* replaced by the
- part of that switch that matched the '*'.
+ part of that switch that matched the '*'. A space will be
+ appended after the last substitution unless there is more
+ text in current sequence.
%{.S:X} substitutes X, if processing a file with suffix S.
%{!.S:X} substitutes X, if NOT processing a file with suffix S.
%{,S:X} substitutes X, if processing a file which will use spec S.
@@ -5375,7 +5378,17 @@
{
if (soft_matched_part[0])
do_spec_1 (soft_matched_part, 1, NULL);
- do_spec_1 (" ", 0, NULL);
+ /* Only insert a space after the substitution if it is at the
+ end of the current sequence. So if:
+
+ "%{foo=*:bar%*}%{foo=*:one%*two}"
+
+ matches -foo=hello then it will produce:
+
+ barhello onehellotwo
+ */
+ if (*p == 0 || *p == '}')
+ do_spec_1 (" ", 0, NULL);
}
else
/* Catch the case where a spec string contains something like
