bc: upgrade to version 3.3.4

This upgrade performs an implicit flush of the output if the script
funcion read() is called, to make sure a prompt that does not end in a
new-line is correctly displayed in line-buffered output mode.

Merge commit '893ecb52db5ed47d6c1e8698334d34e0df651612'

contrib/bc/Makefile.in

@@ -29,7 +29,7 @@
 #
 .POSIX:
 
-VERSION = 3.3.3
+VERSION = 3.3.4
 
 SRC = %%SRC%%
 OBJ = %%OBJ%%

contrib/bc/NEWS.md

@@ -1,5 +1,14 @@
 # News
 
+## 3.3.4
+
+This is a production release that fixes a small bug.
+
+The bug was that output was not flushed before a `read()` call, so prompts
+without a newline on the end were not flushed before the `read()` call.
+
+This is such a tiny bug that users only need to upgrade if they are affected.
+
 ## 3.3.3
 
 This is a production release with one tweak and fixes for manuals.

contrib/bc/README.md

@@ -42,8 +42,7 @@ Systems that are known to work:
 * HP-UX* (except for history)
 
 Please submit bug reports if this `bc` does not build out of the box on any
-system besides Windows. If Windows binaries are needed, they can be found at
-[xstatic][6].
+system besides Windows.
 
 ## Build
 
@@ -52,12 +51,6 @@ This `bc` should build unmodified on any POSIX-compliant system.
 For more complex build requirements than the ones below, see the
 [build manual][5].
 
-### Pre-built Binaries
-
-It is possible to download pre-compiled binaries for a wide list of platforms,
-including Linux- and Windows-based systems, from [xstatic][6]. This link always
-points to the latest release of `bc`.
-
 ### Default
 
 For the default build with optimization, use the following commands in the root
@@ -329,7 +322,6 @@ Folders:
 [1]: https://www.gnu.org/software/bc/
 [4]: ./LICENSE.md
 [5]: ./manuals/build.md
-[6]: https://pkg.musl.cc/bc/
 [7]: ./manuals/algorithms.md
 [8]: https://git.busybox.net/busybox/tree/miscutils/bc.c
 [9]: https://github.com/landley/toybox/blob/master/toys/pending/bc.c

contrib/bc/src/program.c

@@ -1928,6 +1928,10 @@ void bc_program_exec(BcProgram *p) {
 
 			case BC_INST_READ:
 			{
+				// We want to flush output before
+				// this in case there is a prompt.
+				bc_file_flush(&vm.fout);
+
 				bc_program_read(p);
 
 				ip = bc_vec_top(&p->stack);