Filter out files that are not ending in .c from c-sources

cabal-testsuite/PackageTests/CSourcesSanitisation/Main.hs

@@ -0,0 +1,4 @@
+module Main where
+
+main :: IO ()
+main = putStrLn "main"

cabal-testsuite/PackageTests/CSourcesSanitisation/build.test.hs

@@ -0,0 +1,4 @@
+import Test.Cabal.Prelude
+
+main = cabalTest $ do
+  cabal "build"

cabal-testsuite/PackageTests/CSourcesSanitisation/cbits/gwinsz.c

@@ -0,0 +1,18 @@
+#include <sys/ioctl.h>
+
+unsigned long vty_c_get_window_size(int fd) {
+    struct winsize w;
+    if (ioctl (fd, TIOCGWINSZ, &w) >= 0)
+        return (w.ws_row << 16) + w.ws_col;
+    else
+        return 0x190050;
+}
+
+void vty_c_set_window_size(int fd, unsigned long val) {
+    struct winsize w;
+    if (ioctl(fd, TIOCGWINSZ, &w) >= 0) {
+        w.ws_row = val >> 16;
+        w.ws_col = val & 0xFFFF;
+        ioctl(fd, TIOCSWINSZ, &w);
+    }
+}

cabal-testsuite/PackageTests/CSourcesSanitisation/cbits/gwinsz.h

@@ -0,0 +1,2 @@
+unsigned long vty_c_get_window_size(int fd);
+unsigned long vty_c_set_window_size(int fd, unsigned long val);

cabal-testsuite/PackageTests/CSourcesSanitisation/cbits/set_term_timing.c

@@ -0,0 +1,13 @@
+#include <termios.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+void vty_set_term_timing(int fd, int vmin, int vtime)
+{
+    struct termios trm;
+    tcgetattr(fd, &trm);
+    trm.c_cc[VMIN] = vmin;
+    trm.c_cc[VTIME] = vtime;
+    tcsetattr(fd, TCSANOW, &trm);
+}

cabal-testsuite/PackageTests/CSourcesSanitisation/repro.cabal

@@ -0,0 +1,26 @@
+cabal-version:      3.0
+name:               repro
+version:            0.1.0.0
+build-type:         Simple
+
+library
+    default-language: Haskell2010
+    c-sources:        cbits/set_term_timing.c
+                      cbits/gwinsz.h
+                      cbits/gwinsz.c
+    build-depends:    base
+
+library lib2
+    default-language: Haskell2010
+    c-sources:        cbits/set_term_timing.c
+                      cbits/gwinsz.h
+                      cbits/gwinsz.c
+    build-depends:    base
+
+executable exec1
+    main-is: Main.hs
+    default-language: Haskell2010
+    c-sources:        cbits/set_term_timing.c
+                      cbits/gwinsz.h
+                      cbits/gwinsz.c
+    build-depends:    base