Add a dmnsn_unreachable() macro.

Also rename inline.h to compiler.h.

7 files changed, 30 insertions, 14 deletions

diff --git a/libdimension/Makefile.am b/libdimension/Makefile.am
index 35f56f7..c75241e 100644
--- a/libdimension/Makefile.am
+++ b/libdimension/Makefile.am
@@ -32,6 +32,7 @@ nobase_include_HEADERS = dimension.h                                           \
                          dimension/cameras.h                                   \
                          dimension/canvas.h                                    \
                          dimension/color.h                                     \
+                         dimension/compiler.h                                  \
                          dimension/csg.h                                       \
                          dimension/dictionary.h                                \
                          dimension/error.h                                     \
@@ -40,7 +41,6 @@ nobase_include_HEADERS = dimension.h                                           \
                          dimension/future.h                                    \
                          dimension/geometry.h                                  \
                          dimension/gl.h                                        \
-                         dimension/inline.h                                    \
                          dimension/interior.h                                  \
                          dimension/light.h                                     \
                          dimension/lights.h                                    \
@@ -69,7 +69,7 @@ libdimension_la_SOURCES = $(nobase_include_HEADERS)                            \
                           canvas_pigment.c                                     \
                           checker.c                                            \
                           color.c                                              \
-                          compiler.h                                           \
+                          compiler-internal.h                                  \
                           cone.c                                               \
                           cube.c                                               \
                           csg.c                                                \
diff --git a/libdimension/compiler.h b/libdimension/compiler-internal.h
index d6435d0..e59ece2 100644
--- a/libdimension/compiler.h
+++ b/libdimension/compiler-internal.h
@@ -20,7 +20,7 @@
 
 /**
  * @file
- * Compiler abstractions.
+ * Internally-used compiler abstractions.
  */
 
 #include <stdbool.h>
diff --git a/libdimension/dimension-internal.h b/libdimension/dimension-internal.h
index 15a7e4c..eae585d 100644
--- a/libdimension/dimension-internal.h
+++ b/libdimension/dimension-internal.h
@@ -30,7 +30,7 @@
 #define _GNU_SOURCE
 #include "dimension.h"
 #include "refcount-internal.h"
-#include "compiler.h"
+#include "compiler-internal.h"
 #include "profile.h"
 #include "platform.h"
 #include "future-impl.h"
diff --git a/libdimension/dimension.h b/libdimension/dimension.h
index 59b73bd..375c2ec 100644
--- a/libdimension/dimension.h
+++ b/libdimension/dimension.h
@@ -74,7 +74,7 @@ typedef void dmnsn_callback_fn(void *ptr);
 typedef void dmnsn_free_fn(void *ptr);
 
 /* Include all the libdimension headers */
-#include <dimension/inline.h>
+#include <dimension/compiler.h>
 #include <dimension/error.h>
 #include <dimension/malloc.h>
 #include <dimension/refcount.h>
diff --git a/libdimension/dimension/inline.h b/libdimension/dimension/compiler.h
index e17c60e..5ce8ce8 100644
--- a/libdimension/dimension/inline.h
+++ b/libdimension/dimension/compiler.h
@@ -20,10 +20,7 @@
 
 /**
  * @file
- * Inline function support. Handle inlines nicely without cheating and making
- * them static.  The DMNSN_INLINE macro is set appropriately for the version of
- * C you're using, and non-inline versions are emitted in exactly one
- * translation unit when necessary.
+ * Compiler abstractions.
  */
 
 /**
@@ -47,3 +44,9 @@
     #define DMNSN_INLINE static
   #endif
 #endif
+
+#ifdef __GNUC__
+  #define DMNSN_UNREACHABLE() __builtin_unreachable();
+#else
+  #define DMNSN_UNREACHABLE()
+#endif
diff --git a/libdimension/dimension/error.h b/libdimension/dimension/error.h
index ae8ba01..894899a 100644
--- a/libdimension/dimension/error.h
+++ b/libdimension/dimension/error.h
@@ -39,8 +39,11 @@
  * Report an error.
  * @param[in] str       A string to print explaining the error.
  */
-#define dmnsn_error(str)                                        \
-  dmnsn_report_error(true, DMNSN_FUNC, __FILE__, __LINE__, str)
+#define dmnsn_error(str)                                                \
+  do {                                                                  \
+    dmnsn_report_error(true, DMNSN_FUNC, __FILE__, __LINE__, str);      \
+    DMNSN_UNREACHABLE();                                                \
+  } while (0)
 
 /**
  * @def dmnsn_assert
@@ -54,12 +57,23 @@
   #define dmnsn_assert(expr, str)                 \
     do {                                          \
       if (!(expr)) {                              \
-        dmnsn_error((str));  \
+        dmnsn_error((str));                       \
       }                                           \
     } while (0)
 #endif
 
 /**
+ * @def dmnsn_unreachable
+ * Express that a line of code is unreachable.
+ * @param[in] str  A string to print if the line is reached.
+ */
+#ifdef NDEBUG
+  #define dmnsn_unreachable(str) DMNSN_UNREACHABLE()
+#else
+  #define dmnsn_unreachable(str) dmnsn_error((str))
+#endif
+
+/**
  * @internal
  * Called by dmnsn_warning() and dmnsn_error(); don't call directly.
  * @param[in] die   Whether the error is fatal.
diff --git a/libdimension/prtree.c b/libdimension/prtree.c
index c59bcc4..33cb9a2 100644
--- a/libdimension/prtree.c
+++ b/libdimension/prtree.c
@@ -121,8 +121,7 @@ dmnsn_get_coordinate(const dmnsn_prnode * const *node, int comparator)
     return -(*node)->bounding_box.max.z;
 
   default:
-    dmnsn_assert(false, "Invalid comparator.");
-    return 0.0; /* Shut up compiler */
+    dmnsn_unreachable("Invalid comparator.");
   }
 }