Fixed link error when building only shared library.

Details:
- Fixed a linker error that occurred when attempting to compile and link
  the testsuite and/or BLAS test drivers after having configured BLIS to
  only generate a shared library (no static library). The chosen
  solution involved
  (1) adding the local library path, $(BASE_LIB_PATH), to the search
      paths for the shared library via the link option
      -Wl,-rpath,$(BASE_LIB_PATH).
  (2) adding a local symlink to $(BASE_LIB_PATH) that uses the .so major
      version number so that ld would find the shared library at
      execution time.
  Thanks to Sajid Ali for reporting this issue, to Devin Matthews for
  pointing out the need for the -rpath option, and to Devangi Parikh for
  helping Sajid isolate the problem.
- Added #include <ctype.h> to bli_system.h to avoid a compiler warning
  resulting from using toupper() from bli_string.c without a prototype.
  Thanks again to Sajid Ali, whose build log revealed this compiler
  warning.
- Added '*.so.*' to .gitignore.
- CREDITS file update.

.gitignore

@@ -18,6 +18,7 @@
 # since its only contents are .a files.
 *.a
 *.so
+*.so.*
 # test executables
 *.x
 *.pexe

CREDITS

@@ -10,6 +10,7 @@ The BLIS framework was primarily authored by
 but many others have contributed code and feedback, including
 
   Murtaza Ali                               (Texas Instruments)
+  Sajid Ali             @s-sajid-ali        (Northwestern University)
   Erling Andersen       @erling-d-andersen
   Alex Arslan           @ararslan
   Vernon Austel                             (IBM, T.J. Watson Research Center)
@@ -41,7 +42,7 @@ but many others have contributed code and feedback, including
   Dave Love             @loveshack
   Tze Meng Low                              (The University of Texas at Austin)
   Nisanth Padinharepatt                     (AMD)
-  Devangi Parikh                            (The University of Texas at Austin)
+  Devangi Parikh        @dnparikh           (The University of Texas at Austin)
   Elmar Peise           @elmar-peise        (RWTH-Aachen)
   Clément Pernet        @ClementPernet
   Ilya Polkovnichenko

Makefile

@@ -130,7 +130,8 @@ MK_LIBS_INST              += $(LIBBLIS_A_INST)
 MK_LIBS_SYML              +=
 endif
 ifeq ($(MK_ENABLE_SHARED),yes)
-MK_LIBS                   += $(LIBBLIS_SO_PATH)
+MK_LIBS                   += $(LIBBLIS_SO_PATH) \
+                             $(LIBBLIS_SO_MAJ_PATH)
 MK_LIBS_INST              += $(LIBBLIS_SO_MMB_INST)
 MK_LIBS_SYML              += $(LIBBLIS_SO_INST) \
                              $(LIBBLIS_SO_MAJ_INST)
@@ -584,7 +585,7 @@ endif
 endif
 
 
-# --- Dynamic library linker rules ---
+# --- Shared library linker rules ---
 
 $(LIBBLIS_SO_PATH): $(MK_BLIS_OBJS)
 ifeq ($(ENABLE_VERBOSE),yes)
@@ -607,6 +608,20 @@ else
 endif
 endif
 
+# Local symlink for shared library.
+# NOTE: We use a '.loc' suffix to avoid filename collisions in case this
+# rule is executed concurrently with the install-lib-symlinks rule, which
+# also creates symlinks in the current directory (before installing them).
+$(LIBBLIS_SO_MAJ_PATH): $(LIBBLIS_SO_PATH)
+ifeq ($(ENABLE_VERBOSE),yes)
+	$(SYMLINK) $(<F) $(@F).loc
+	$(MV) $(@F).loc $(BASE_LIB_PATH)/$(@F)
+else # ifeq ($(ENABLE_VERBOSE),no)
+	@echo "Creating symlink $@"
+	@$(SYMLINK) $(<F) $(@F).loc
+	@$(MV) $(@F).loc $(BASE_LIB_PATH)/$(@F)
+endif
+
 
 # --- BLAS test suite rules ---
 

common.mk

@@ -322,6 +322,12 @@ LIBBLIS_SO         := $(LIBBLIS).$(SHLIB_EXT)
 LIBBLIS_A_PATH     := $(BASE_LIB_PATH)/$(LIBBLIS_A)
 LIBBLIS_SO_PATH    := $(BASE_LIB_PATH)/$(LIBBLIS_SO)
 
+# Create a filepath to a local symlink to the soname--that is, the same as
+# LIBBLIS_SO_PATH except with the .so major version number. Since the shared
+# library lists its soname as 'libblis.so.n', where n is the .so major version
+# number, a symlink in BASE_LIB_PATH is needed so that ld can find the local
+# shared library when the testsuite is run via 'make test' or 'make check'.
+LIBBLIS_SO_MAJ_PATH := $(BASE_LIB_PATH)/$(LIBBLIS_SO).$(SO_MAJOR)
 
 
 #
@@ -388,8 +394,8 @@ ifeq ($(DEBUG_TYPE),sde)
 LDFLAGS    := $(filter-out $(LIBMEMKIND),$(LDFLAGS))
 endif
 
-# The default flag for creating shared objects is different for Linux and
-# OS X.
+# Specify the shared library's 'soname' field.
+# NOTE: The flag for creating shared objects is different for Linux and OS X.
 ifeq ($(OS_NAME),Darwin)
 SOFLAGS    := -dynamiclib
 SOFLAGS    += -Wl,-install_name,$(LIBBLIS_SO).$(SO_MAJOR)
@@ -398,15 +404,14 @@ SOFLAGS    := -shared
 SOFLAGS    += -Wl,-soname,$(LIBBLIS_SO).$(SO_MAJOR)
 endif
 
-# Specify the shared library's 'soname' field.
-
-# Decide which library to link to for things like the testsuite. Default
-# to the static library, unless only the shared library was enabled, in
-# which case we use the shared library.
+# Decide which library to link to for things like the testsuite and BLIS test
+# drivers. We default to the static library, unless only the shared library was
+# enabled, in which case we use the shared library.
 LIBBLIS_LINK   := $(LIBBLIS_A_PATH)
 ifeq ($(MK_ENABLE_SHARED),yes)
 ifeq ($(MK_ENABLE_STATIC),no)
 LIBBLIS_LINK   := $(LIBBLIS_SO_PATH)
+LDFLAGS        += -Wl,-rpath,$(BASE_LIB_PATH)
 endif
 endif
 

frame/include/bli_system.h

@@ -42,6 +42,7 @@
 #include <stdarg.h>
 #include <float.h>
 #include <errno.h>
+#include <ctype.h>
 
 // Determine if we are on a 64-bit or 32-bit architecture.
 #if defined(_M_X64) || defined(__x86_64) || defined(__aarch64__) || \